\FBMYSQL\FR
Section: MySQL Database System (1)Updated: 12/16/2011
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NAME
mysql - the MySQL command-line toolSYNOPSIS
- mysql [options] db_name
DESCRIPTION
mysql
If you have problems due to insufficient memory for large result sets, use the --quick option. This forces mysql to retrieve results from the server a row at a time rather than retrieving the entire result set and buffering it in memory before displaying it. This is done by returning the result set using the mysql_use_result() C API function in the client/server library rather than mysql_store_result().
Using mysql is very easy. Invoke it from the prompt of your command interpreter as follows:
-
shell> mysql db_name
Or:
-
shell> mysql --user=user_name --password=your_password db_name
Then type an SQL statement, end it with lq;rq, \g, or \G and press Enter.
As of MySQL 5.1.10, typing Control+C causes mysql to attempt to kill the current statement. If this cannot be done, or Control+C is typed again before the statement is killed, mysql exits. Previously, Control+C caused mysql to exit in all cases.
You can execute SQL statements in a script file (batch file) like this:
-
shell> mysql db_name < script.sql > output.tab
On Unix, the mysql client writes a record of executed statements to a history file. See the section called lqMYSQL HISTORY FILErq.
MYSQL OPTIONS
mysql supports the following options, which can be specified on the command line or in the [mysql] and [client] groups of an option file. mysql also supports the options for processing option files described at Section <IP_ADDRESS>.1, lqCommand-Line Options that Affect Option-File Handlingrq.
-
*
--help,
-?
Display a help message and exit.
-
*
--auto-rehash
Enable automatic rehashing. This option is on by default, which enables database, table, and column name completion. Use --disable-auto-rehash to disable rehashing. That causes mysql to start faster, but you must issue the rehash command if you want to use name completion.
To complete a name, enter the first part and press Tab. If the name is unambiguous, mysql completes it. Otherwise, you can press Tab again to see the possible names that begin with what you have typed so far. Completion does not occur if there is no default database.
-
*
--batch,
-B
Print results using tab as the column separator, with each row on a new line. With this option, mysql does not use the history file.
Batch mode results in nontabular output format and escaping of special characters. Escaping may be disabled by using raw mode; see the description for the --raw option.
-
*
--bind-address=ip_address
On a computer having multiple network interfaces, this option can be used to select which interface is employed when connecting to the MySQL server.
This option is supported only in the version of the mysql client that is supplied with MySQL Cluster, beginning with MySQL Cluster NDB 6.3.4. It is not available in standard MySQL 5.1 releases.
-
*
--character-sets-dir=path
The directory where character sets are installed. See Section 9.5, lqCharacter Set Configurationrq.
-
*
--column-names
Write column names in results.
-
*
--column-type-info,
-m
Display result set metadata. This option was added in MySQL 5.1.14. (Before that, use --debug-info.) The -m short option was added in MySQL 5.1.21.
-
*
--comments,
-c
Whether to preserve comments in statements sent to the server. The default is --skip-comments (discard comments), enable with --comments (preserve comments). This option was added in MySQL 5.1.23.
-
*
--compress,
-C
Compress all information sent between the client and the server if both support compression.
-
*
--database=db_name,
-D db_name
The database to use. This is useful primarily in an option file.
-
*
--debug[=debug_options],
-# [debug_options]
Write a debugging log. A typical debug_options string is 'd:t:o,file_name'. The default is 'd:t:o,/tmp/mysql.trace'.
-
*
--debug-check
Print some debugging information when the program exits. This option was added in MySQL 5.1.21.
-
*
--debug-info,
-T
Before MySQL 5.1.14, this option prints debugging information and memory and CPU usage statistics when the program exits, and also causes display of result set metadata during execution. As of MySQL 5.1.14, use --column-type-info to display result set metadata.
-
*
--default-character-set=charset_name
Use charset_name as the default character set for the client and connection.
A common issue that can occur when the operating system uses utf8 or another multi-byte character set is that output from the mysql client is formatted incorrectly, due to the fact that the MySQL client uses the latin1 character set by default. You can usually fix such issues by using this option to force the client to use the system character set instead.
See Section 9.5, lqCharacter Set Configurationrq, for more information.
-
*
--delimiter=str
Set the statement delimiter. The default is the semicolon character (lq;rq).
-
*
--disable-named-commands
Disable named commands. Use the \* form only, or use named commands only at the beginning of a line ending with a semicolon (lq;rq). mysql starts with this option enabled by default. However, even with this option, long-format commands still work from the first line. See the section called lqMYSQL COMMANDSrq.
-
*
--execute=statement,
-e statement
Execute the statement and quit. The default output format is like that produced with --batch. See Section <IP_ADDRESS>, lqUsing Options on the Command Linerq, for some examples. With this option, mysql does not use the history file.
-
*
--force,
-f
Continue even if an SQL error occurs.
-
*
--host=host_name,
-h host_name
Connect to the MySQL server on the given host.
-
*
--html,
-H
Produce HTML output.
-
*
--ignore-spaces,
-i
Ignore spaces after function names. The effect of this is described in the discussion for the IGNORE_SPACE SQL mode (see Section 5.1.6, lqServer SQL Modesrq).
-
*
--line-numbers
Write line numbers for errors. Disable this with --skip-line-numbers.
-
*
--local-infile[={0|1}]
Enable or disable LOCAL capability for LOAD DATA INFILE. With no value, the option enables LOCAL. The option may be given as --local-infile=0 or --local-infile=1 to explicitly disable or enable LOCAL. Enabling LOCAL has no effect if the server does not also support it.
-
*
--named-commands,
-G
Enable named mysql commands. Long-format commands are permitted, not just short-format commands. For example, quit and \q both are recognized. Use --skip-named-commands to disable named commands. See the section called lqMYSQL COMMANDSrq.
-
*
--no-auto-rehash,
-A
This has the same effect as -skip-auto-rehash. See the description for --auto-rehash.
-
*
--no-beep,
-b
Do not beep when errors occur.
-
*
--no-named-commands,
-g
Deprecated, use --disable-named-commands instead. --no-named-commands is removed in MySQL 5.5.
-
*
--no-pager
Deprecated form of --skip-pager. See the --pager option. --no-pager is removed in MySQL 5.5.
-
*
--no-tee
Deprecated form of --skip-tee. See the --tee option. --no-tee is removed in MySQL 5.5.
-
*
--one-database,
-o
Ignore statements except those that occur while the default database is the one named on the command line. This option is rudimentary and should be used with care. Statement filtering is based only on USE statements.
Initially, mysql executes statements in the input because specifying a database db_name on the command line is equivalent to inserting USE db_name at the beginning of the input. Then, for each USE statement encountered, mysql accepts or rejects following statements depending on whether the database named is the one on the command line. The content of the statements is immaterial.
Suppose that mysql is invoked to process this set of statements:
-
DELETE FROM db2.t2; USE db2; DROP TABLE db1.t1; CREATE TABLE db1.t1 (i INT); USE db1; INSERT INTO t1 (i) VALUES(1); CREATE TABLE db2.t1 (j INT);
If the command line is mysql --force --one-database db1, mysql handles the input as follows:
- * The DELETE statement is executed because the default database is db1, even though the statement names a table in a different database.
- * The DROP TABLE and CREATE TABLE statements are not executed because the default database is not db1, even though the statements name a table in db1.
- * The INSERT and CREATE TABLE statements are executed because the default database is db1, even though the CREATE TABLE statement names a table in a different database.
-
-
*
--pager[=command]
Use the given command for paging query output. If the command is omitted, the default pager is the value of your PAGER environment variable. Valid pagers are less, more, cat [> filename], and so forth. This option works only on Unix and only in interactive mode. To disable paging, use --skip-pager. the section called lqMYSQL COMMANDSrq, discusses output paging further.
-
*
--password[=password],
-p[password]
The password to use when connecting to the server. If you use the short option form (-p), you cannot have a space between the option and the password. If you omit the password value following the --password or -p option on the command line, mysql prompts for one.
Specifying a password on the command line should be considered insecure. See Section <IP_ADDRESS>, lqEnd-User Guidelines for Password Securityrq. You can use an option file to avoid giving the password on the command line.
-
*
--pipe,
-W
On Windows, connect to the server using a named pipe. This option applies only if the server supports named-pipe connections.
-
*
--port=port_num,
-P port_num
The TCP/IP port number to use for the connection.
-
*
--prompt=format_str
Set the prompt to the specified format. The default is mysql>. The special sequences that the prompt can contain are described in the section called lqMYSQL COMMANDSrq.
-
*
--protocol={TCP|SOCKET|PIPE|MEMORY}
The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the permissible values, see Section 4.2.2, lqConnecting to the MySQL Serverrq.
-
*
--quick,
-q
Do not cache each query result, print each row as it is received. This may slow down the server if the output is suspended. With this option, mysql does not use the history file.
-
*
--raw,
-r
For tabular output, the lqboxingrq around columns enables one column value to be distinguished from another. For nontabular output (such as is produced in batch mode or when the --batch or --silent option is given), special characters are escaped in the output so they can be identified easily. Newline, tab, NUL, and backslash are written as \n, \t, \0, and \\. The --raw option disables this character escaping.
The following example demonstrates tabular versus nontabular output and the use of raw mode to disable escaping:
-
% mysql mysql> SELECT CHAR(92); +----------+ | CHAR(92) | +----------+ | \ | +----------+ % mysql -s mysql> SELECT CHAR(92); CHAR(92) \\ % mysql -s -r mysql> SELECT CHAR(92); CHAR(92) \
-
-
*
--reconnect
If the connection to the server is lost, automatically try to reconnect. A single reconnect attempt is made each time the connection is lost. To suppress reconnection behavior, use --skip-reconnect.
-
*
--safe-updates,
--i-am-a-dummy,
-U
Permit only those UPDATE and DELETE statements that specify which rows to modify by using key values. If you have set this option in an option file, you can override it by using --safe-updates on the command line. See the section called lqMYSQL TIPSrq, for more information about this option.
-
*
--secure-auth
Do not send passwords to the server in old (pre-4.1.1) format. This prevents connections except for servers that use the newer password format.
-
*
--show-warnings
Cause warnings to be shown after each statement if there are any. This option applies to interactive and batch mode.
-
*
--sigint-ignore
Ignore SIGINT signals (typically the result of typing Control+C).
-
*
--silent,
-s
Silent mode. Produce less output. This option can be given multiple times to produce less and less output.
This option results in nontabular output format and escaping of special characters. Escaping may be disabled by using raw mode; see the description for the --raw option.
-
*
--skip-column-names,
-N
Do not write column names in results.
-
*
--skip-line-numbers,
-L
Do not write line numbers for errors. Useful when you want to compare result files that include error messages.
-
*
--socket=path,
-S path
For connections to localhost, the Unix socket file to use, or, on Windows, the name of the named pipe to use.
-
*
--ssl*
Options that begin with --ssl specify whether to connect to the server using SSL and indicate where to find SSL keys and certificates. See Section <IP_ADDRESS>, lqSSL Command Optionsrq.
-
*
--table,
-t
Display output in table format. This is the default for interactive use, but can be used to produce table output in batch mode.
-
*
--tee=file_name
Append a copy of output to the given file. This option works only in interactive mode. the section called lqMYSQL COMMANDSrq, discusses tee files further.
-
*
--unbuffered,
-n
Flush the buffer after each query.
-
*
--user=user_name,
-u user_name
The MySQL user name to use when connecting to the server.
-
*
--verbose,
-v
Verbose mode. Produce more output about what the program does. This option can be given multiple times to produce more and more output. (For example, -v -v -v produces table output format even in batch mode.)
-
*
--version,
-V
Display version information and exit.
-
*
--vertical,
-E
Print query output rows vertically (one line per column value). Without this option, you can specify vertical output for individual statements by terminating them with \G.
-
*
--wait,
-w
If the connection cannot be established, wait and retry instead of aborting.
-
*
--xml,
-X
Produce XML output.
-
Note
Prior to MySQL 5.1.12, there was no differentiation in the output when using this option between columns containing the NULL value and columns containing the string literal 'NULL'; both were represented as
-
<field name="column_name">NULL</field>
Beginning with MySQL 5.1.12, the output when --xml is used with mysql matches that of mysqldump --xml. See mysqldump(1) for details.
Beginning with MySQL 5.1.18, the XML output also uses an XML namespace, as shown here:
-
shell> mysql --xml -uroot -e "SHOW VARIABLES LIKE 'version%'" <?xml version="1.0"?> <resultset statement="SHOW VARIABLES LIKE 'version%'" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <row> <field name="Variable_name">version</field> <field name="Value">5.0.40-debug</field> </row> <row> <field name="Variable_name">version_comment</field> <field name="Value">Source distribution</field> </row> <row> <field name="Variable_name">version_compile_machine</field> <field name="Value">i686</field> </row> <row> <field name="Variable_name">version_compile_os</field> <field name="Value">suse-linux-gnu</field> </row> </resultset>
(See Bug #25946.)
-
You can also set the following variables by using --var_name=value. The --set-variable format is deprecated and is removed in MySQL 5.5.
-
*
connect_timeout
The number of seconds before connection timeout. (Default value is 0.)
-
*
max_allowed_packet
The maximum packet length to send to or receive from the server. (Default value is 16MB.)
-
*
max_join_size
The automatic limit for rows in a join when using --safe-updates. (Default value is 1,000,000.)
-
*
net_buffer_length
The buffer size for TCP/IP and socket communication. (Default value is 16KB.)
-
*
select_limit
The automatic limit for SELECT statements when using --safe-updates. (Default value is 1,000.)
MYSQL COMMANDS
mysql sends each SQL statement that you issue to the server to be executed. There is also a set of commands that mysql itself interprets. For a list of these commands, type help or \h at the mysql> prompt:
-
mysql> help List of all MySQL commands: Note that all text commands must be first on line and end with ';' ? (\?) Synonym for `help'. clear (\c) Clear command. connect (\r) Reconnect to the server. Optional arguments are db and host. delimiter (\d) Set statement delimiter. edit (\e) Edit command with $EDITOR. ego (\G) Send command to mysql server, display result vertically. exit (\q) Exit mysql. Same as quit. go (\g) Send command to mysql server. help (\h) Display this help. nopager (\n) Disable pager, print to stdout. notee (\t) Don't write into outfile. pager (\P) Set PAGER [to_pager]. Print the query results via PAGER. print (\p) Print current command. prompt (\R) Change your mysql prompt. quit (\q) Quit mysql. rehash (\#) Rebuild completion hash. source (\.) Execute an SQL script file. Takes a file name as an argument. status (\s) Get status information from the server. system (\!) Execute a system shell command. tee (\T) Set outfile [to_outfile]. Append everything into given outfile. use (\u) Use another database. Takes database name as argument. charset (\C) Switch to another charset. Might be needed for processing binlog with multi-byte charsets. warnings (\W) Show warnings after every statement. nowarning (\w) Don't show warnings after every statement. For server side help, type 'help contents'
Each command has both a long and short form. The long form is not case sensitive; the short form is. The long form can be followed by an optional semicolon terminator, but the short form should not.
The use of short-form commands within multi-line /* ... */ comments is not supported.
-
*
help [arg],
\h [arg],
\? [arg],
? [arg]
Display a help message listing the available mysql commands.
If you provide an argument to the help command, mysql uses it as a search string to access server-side help from the contents of the MySQL Reference Manual. For more information, see the section called lqMYSQL SERVER-SIDE HELPrq.
-
*
charset charset_name,
\C charset_name
Change the default character set and issue a SET NAMES statement. This enables the character set to remain synchronized on the client and server if mysql is run with auto-reconnect enabled (which is not recommended), because the specified character set is used for reconnects. This command was added in MySQL 5.1.7.
-
*
clear,
\c
Clear the current input. Use this if you change your mind about executing the statement that you are entering.
-
*
connect [db_name host_name]],
\r [db_name host_name]]
Reconnect to the server. The optional database name and host name arguments may be given to specify the default database or the host where the server is running. If omitted, the current values are used.
-
*
delimiter str,
\d str
Change the string that mysql interprets as the separator between SQL statements. The default is the semicolon character (lq;rq).
The delimiter string can be specified as an unquoted or quoted argument on the delimiter command line. Quoting can be done with either single quote ('), douple quote ("), or backtick (`) characters. To include a quote within a quoted string, either quote the string with a different quote character or escape the quote with a backslash (lq\rq) character. Backslash should be avoided outside of quoted strings because it is the escape character for MySQL. For an unquoted argument, the delimiter is read up to the first space or end of line. For a quoted argument, the delimiter is read up to the matching quote on the line.
mysql interprets instances of the delimiter string as a statement delimiter anywhere it occurs, except within quoted strings. Be careful about defining a delimiter that might occur within other words. For example, if you define the delimiter as X, you will be unable to use the word INDEX in statements. mysql interprets this as INDE followed by the delimiter X.
When the delimiter recognized by mysql is set to something other than the default of lq;rq, instances of that character are sent to the server without interpretation. However, the server itself still interprets lq;rq as a statement delimiter and processes statements accordingly. This behavior on the server side comes into play for multiple-statement execution (see Section 20.9.12, lqC API Support for Multiple Statement Executionrq), and for parsing the body of stored procedures and functions, triggers, and events (see Section 18.1, lqDefining Stored Programsrq).
-
*
edit,
\e
Edit the current input statement. mysql checks the values of the EDITOR and VISUAL environment variables to determine which editor to use. The default editor is vi if neither variable is set.
The edit command works only in Unix.
-
*
ego,
\G
Send the current statement to the server to be executed and display the result using vertical format.
-
*
exit,
\q
Exit mysql.
-
*
go,
\g
Send the current statement to the server to be executed.
-
*
nopager,
\n
Disable output paging. See the description for pager.
The nopager command works only in Unix.
-
*
notee,
\t
Disable output copying to the tee file. See the description for tee.
-
*
nowarning,
\w
Enable display of warnings after each statement.
-
*
pager [command],
\P [command]
Enable output paging. By using the --pager option when you invoke mysql, it is possible to browse or search query results in interactive mode with Unix programs such as less, more, or any other similar program. If you specify no value for the option, mysql checks the value of the PAGER environment variable and sets the pager to that. Pager functionality works only in interactive mode.
Output paging can be enabled interactively with the pager command and disabled with nopager. The command takes an optional argument; if given, the paging program is set to that. With no argument, the pager is set to the pager that was set on the command line, or stdout if no pager was specified.
Output paging works only in Unix because it uses the popen() function, which does not exist on Windows. For Windows, the tee option can be used instead to save query output, although it is not as convenient as pager for browsing output in some situations.
-
*
print,
\p
Print the current input statement without executing it.
-
*
prompt [str],
\R [str]
Reconfigure the mysql prompt to the given string. The special character sequences that can be used in the prompt are described later in this section.
If you specify the prompt command with no argument, mysql resets the prompt to the default of mysql>.
-
*
quit,
\q
Exit mysql.
-
*
rehash,
\#
Rebuild the completion hash that enables database, table, and column name completion while you are entering statements. (See the description for the --auto-rehash option.)
-
*
source file_name,
\. file_name
Read the named file and executes the statements contained therein. On Windows, you can specify path name separators as / or \\.
-
*
status,
\s
Provide status information about the connection and the server you are using. If you are running in --safe-updates mode, status also prints the values for the mysql variables that affect your queries.
-
*
system command,
\! command
Execute the given command using your default command interpreter.
The system command works only in Unix.
-
*
tee [file_name],
\T [file_name]
By using the --tee option when you invoke mysql, you can log statements and their output. All the data displayed on the screen is appended into a given file. This can be very useful for debugging purposes also. mysql flushes results to the file after each statement, just before it prints its next prompt. Tee functionality works only in interactive mode.
You can enable this feature interactively with the tee command. Without a parameter, the previous file is used. The tee file can be disabled with the notee command. Executing tee again re-enables logging.
-
*
use db_name,
\u db_name
Use db_name as the default database.
-
*
warnings,
\W
Enable display of warnings after each statement (if there are any).
Here are a few tips about the pager command:
-
*
You can use it to write to a file and the results go only to the file:
-
mysql> pager cat > /tmp/log.txt
You can also pass any options for the program that you want to use as your pager:
-
mysql> pager less -n -i -S
-
-
*
In the preceding example, note the
-S
option. You may find it very useful for browsing wide query results. Sometimes a very wide result set is difficult to read on the screen. The
-S
option to
less
can make the result set much more readable because you can scroll it horizontally using the left-arrow and right-arrow keys. You can also use
-S
interactively within
less
to switch the horizontal-browse mode on and off. For more information, read the
less
manual page:
-
shell> man less
-
-
*
The
-F
and
-X
options may be used with
less
to cause it to exit if output fits on one screen, which is convenient when no scrolling is necessary:
-
mysql> pager less -n -i -S -F -X
-
-
*
You can specify very complex pager commands for handling query output:
-
mysql> pager cat | tee /dr1/tmp/res.txt \ | tee /dr2/tmp/res2.txt | less -n -i -S
In this example, the command would send query results to two files in two different directories on two different file systems mounted on /dr1 and /dr2, yet still display the results onscreen using less.
-
You can also combine the tee and pager functions. Have a tee file enabled and pager set to less, and you are able to browse the results using the less program and still have everything appended into a file the same time. The difference between the Unix tee used with the pager command and the mysql built-in tee command is that the built-in tee works even if you do not have the Unix tee available. The built-in tee also logs everything that is printed on the screen, whereas the Unix tee used with pager does not log quite that much. Additionally, tee file logging can be turned on and off interactively from within mysql. This is useful when you want to log some queries to a file, but not others.
The prompt command reconfigures the default mysql> prompt. The string for defining the prompt can contain the following special sequences.
| Option |
Description
|
| \c |
A counter that increments for each statement you issue
|
| \D |
The full current date
|
| \d |
The default database
|
| \h |
The server host
|
| \l |
The current delimiter (new in 5.1.12)
|
| \m |
Minutes of the current time
|
| \n |
A newline character
|
| \O |
The current month in three-letter format (Jan, Feb, ...)
|
| \o |
The current month in numeric format
|
| \P |
am/pm
|
| \p |
The current TCP/IP port or socket file
|
| \R |
The current time, in 24-hour military time (0-23)
|
| \r |
The current time, standard 12-hour time (1-12)
|
| \S |
Semicolon
|
| \s |
Seconds of the current time
|
| \t |
A tab character
|
| \U |
Your full
user_name@host_name
account name
|
| \u |
Your user name
|
| \v |
The server version
|
| \w |
The current day of the week in three-letter format (Mon, Tue, ...)
|
| \Y |
The current year, four digits
|
| \y |
The current year, two digits
|
| \_ |
A space
|
| \ |
A space (a space follows the backslash)
|
| \' |
Single quote
|
| \" |
Double quote
|
| \\ |
A literal lq\rq backslash character
|
| \x |
x, for any
lqxrq
not listed above
|
You can set the prompt in several ways:
-
*
Use an environment variable.
You can set the
MYSQL_PS1
environment variable to a prompt string. For example:
-
shell> export MYSQL_PS1="(\u@\h) [\d]> "
-
-
*
Use a command-line option.
You can set the
--prompt
option on the command line to
mysql. For example:
-
shell> mysql --prompt="(\u@\h) [\d]> " (user@host) [database]>
-
-
*
Use an option file.
You can set the
prompt
option in the
[mysql]
group of any MySQL option file, such as
/etc/my.cnf
or the
.my.cnf
file in your home directory. For example:
-
[mysql] prompt=(\\u@\\h) [\\d]>\\_
In this example, note that the backslashes are doubled. If you set the prompt using the prompt option in an option file, it is advisable to double the backslashes when using the special prompt options. There is some overlap in the set of permissible prompt options and the set of special escape sequences that are recognized in option files. (The rules for escape sequences in option files are listed in Section <IP_ADDRESS>, lqUsing Option Filesrq.) The overlap may cause you problems if you use single backslashes. For example, \s is interpreted as a space rather than as the current seconds value. The following example shows how to define a prompt within an option file to include the current time in HH:MM:SS> format:
-
[mysql] prompt="\\r:\\m:\\s> "
-
-
*
Set the prompt interactively.
You can change your prompt interactively by using the
prompt
(or
\R) command. For example:
-
mysql> prompt (\u@\h) [\d]>\_ PROMPT set to '(\u@\h) [\d]>\_' (user@host) [database]> (user@host) [database]> prompt Returning to default PROMPT of mysql> mysql>
-
MYSQL HISTORY FILE
On Unix, the mysql client writes a record of executed statements to a history file. By default, this file is named .mysql_history and is created in your home directory. To specify a different file, set the value of the MYSQL_HISTFILE environment variable.
The .mysql_history should be protected with a restrictive access mode because sensitive information might be written to it, such as the text of SQL statements that contain passwords. See Section <IP_ADDRESS>, lqEnd-User Guidelines for Password Securityrq.
It is possible to suppress logging of statements to the history file by using the --batch or --execute option.
If you do not want to maintain a history file, first remove .mysql_history if it exists, and then use either of the following techniques:
- * Set the MYSQL_HISTFILE variable to /dev/null. To cause this setting to take effect each time you log in, put the setting in one of your shell's startup files.
-
*
Create
.mysql_history
as a symbolic link to
/dev/null:
-
shell> ln -s /dev/null $HOME/.mysql_history
You need do this only once.
-
MYSQL SERVER-SIDE HELP
-
mysql> help search_string
If you provide an argument to the help command, mysql uses it as a search string to access server-side help from the contents of the MySQL Reference Manual. The proper operation of this command requires that the help tables in the mysql database be initialized with help topic information (see Section 5.1.8, lqServer-Side Helprq).
If there is no match for the search string, the search fails:
-
mysql> help me Nothing found Please try to run 'help contents' for a list of all accessible topics
Use help contents to see a list of the help categories:
-
mysql> help contents You asked for help about help category: "Contents" For more information, type 'help <item>', where <item> is one of the following categories: Account Management Administration Data Definition Data Manipulation Data Types Functions Functions and Modifiers for Use with GROUP BY Geographic Features Language Structure Plugins Storage Engines Stored Routines Table Maintenance Transactions Triggers
If the search string matches multiple items, mysql shows a list of matching topics:
-
mysql> help logs Many help items for your request exist. To make a more specific request, please type 'help <item>', where <item> is one of the following topics: SHOW SHOW BINARY LOGS SHOW ENGINE SHOW LOGS
Use a topic as the search string to see the help entry for that topic:
-
mysql> help show binary logs Name: 'SHOW BINARY LOGS' Description: Syntax: SHOW BINARY LOGS SHOW MASTER LOGS Lists the binary log files on the server. This statement is used as part of the procedure described in [purge-binary-logs], that shows how to determine which logs can be purged. mysql> SHOW BINARY LOGS; +---------------+-----------+ | Log_name | File_size | +---------------+-----------+ | binlog.000015 | 724935 | | binlog.000016 | 733481 | +---------------+-----------+
EXECUTING SQL STATEMENTS FROM A TEXT FILE
The mysql client typically is used interactively, like this:
-
shell> mysql db_name
However, it is also possible to put your SQL statements in a file and then tell mysql to read its input from that file. To do so, create a text file text_file that contains the statements you wish to execute. Then invoke mysql as shown here:
-
shell> mysql db_name < text_file
If you place a USE db_name statement as the first statement in the file, it is unnecessary to specify the database name on the command line:
-
shell> mysql < text_file
If you are already running mysql, you can execute an SQL script file using the source command or \. command:
-
mysql> source file_name mysql> \. file_name
Sometimes you may want your script to display progress information to the user. For this you can insert statements like this:
-
SELECT '<info_to_display>' AS ' ';
The statement shown outputs <info_to_display>.
You can also invoke mysql with the --verbose option, which causes each statement to be displayed before the result that it produces.
As of MySQL 5.1.23, mysql ignores Unicode byte order mark (BOM) characters at the beginning of input files. Previously, it read them and sent them to the server, resulting in a syntax error. Presence of a BOM does not cause mysql to change its default character set. To do that, invoke mysql with an option such as --default-character-set=utf8.
For more information about batch mode, see Section 3.5, lqUsing mysql in Batch Moderq.
MYSQL TIPS
This section describes some techniques that can help you use mysql more effectively.
Displaying Query Results Vertically
Some query results are much more readable when displayed vertically, instead of in the usual horizontal table format. Queries can be displayed vertically by terminating the query with \G instead of a semicolon. For example, longer text values that include newlines often are much easier to read with vertical output:
-
mysql> SELECT * FROM mails WHERE LENGTH(txt) < 300 LIMIT 300,1\G *************************** 1. row *************************** msg_nro: 3068 date: 2000-03-01 23:29:50 time_zone: +0200 mail_from: Monty reply<EMAIL_ADDRESS>mail_to: "Thimble Smith"<EMAIL_ADDRESS>sbj: UTF-8 txt: >>>>> "Thimble" == Thimble Smith writes: Thimble> Hi. I think this is a good idea. Is anyone familiar Thimble> with UTF-8 or Unicode? Otherwise, I'll put this on my Thimble> TODO list and see what happens. Yes, please do that. Regards, Monty file: inbox-jani-1 hash: 190402944 1 row in set (0.09 sec)
Using the --safe-updates Option
For beginners, a useful startup option is --safe-updates (or --i-am-a-dummy, which has the same effect). It is helpful for cases when you might have issued a DELETE FROM tbl_name statement but forgotten the WHERE clause. Normally, such a statement deletes all rows from the table. With --safe-updates, you can delete rows only by specifying the key values that identify them. This helps prevent accidents.
When you use the --safe-updates option, mysql issues the following statement when it connects to the MySQL server:
-
SET sql_safe_updates=1, sql_select_limit=1000, sql_max_join_size=1000000;
See Section 5.1.3, lqServer System Variablesrq.
The SET statement has the following effects:
-
*
You are not permitted to execute an
UPDATE
or
DELETE
statement unless you specify a key constraint in the
WHERE
clause or provide a
LIMIT
clause (or both). For example:
-
UPDATE tbl_name SET not_key_column=val WHERE key_column=val; UPDATE tbl_name SET not_key_column=val LIMIT 1;
-
- * The server limits all large SELECT results to 1,000 rows unless the statement includes a LIMIT clause.
- * The server aborts multiple-table SELECT statements that probably need to examine more than 1,000,000 row combinations.
To specify limits different from 1,000 and 1,000,000, you can override the defaults by using the --select_limit and --max_join_size options:
-
shell> mysql --safe-updates --select_limit=500 --max_join_size=10000
Disabling mysql Auto-Reconnect
If the mysql client loses its connection to the server while sending a statement, it immediately and automatically tries to reconnect once to the server and send the statement again. However, even if mysql succeeds in reconnecting, your first connection has ended and all your previous session objects and settings are lost: temporary tables, the autocommit mode, and user-defined and session variables. Also, any current transaction rolls back. This behavior may be dangerous for you, as in the following example where the server was shut down and restarted between the first and second statements without you knowing it:
-
mysql> SET @a=1; Query OK, 0 rows affected (0.05 sec) mysql> INSERT INTO t VALUES(@a); ERROR 2006: MySQL server has gone away No connection. Trying to reconnect... Connection id: 1 Current database: test Query OK, 1 row affected (1.30 sec) mysql> SELECT * FROM t; +------+ | a | +------+ | NULL | +------+ 1 row in set (0.05 sec)
The @a user variable has been lost with the connection, and after the reconnection it is undefined. If it is important to have mysql terminate with an error if the connection has been lost, you can start the mysql client with the --skip-reconnect option.
For more information about auto-reconnect and its effect on state information when a reconnection occurs, see Section 20.9.11, lqControlling Automatic Reconnection Behaviorrq.
COPYRIGHT
Copyright © 1997, 2011, Oracle and/or its affiliates. All rights reserved.
This documentation is free software; you can redistribute it and/or modify it only under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License.
This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with the program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see http://www.gnu.org/licenses/.
SEE ALSO
For more information, please refer to the MySQL Reference Manual, which may already be installed locally and which is also available online at http://dev.mysql.com/doc/.AUTHOR
Oracle Corporation (http://dev.mysql.com/).
Index
- NAME
- SYNOPSIS
- DESCRIPTION
- MYSQL OPTIONS
- MYSQL COMMANDS
- MYSQL HISTORY FILE
- MYSQL SERVER-SIDE HELP
- EXECUTING SQL STATEMENTS FROM A TEXT FILE
- MYSQL TIPS
- COPYRIGHT
- SEE ALSO
- AUTHOR
This document was created by man2html, using the manual pages.
Time: 05:29:06 GMT, December 24, 2015


Map Edit
Add row
Delete select row
Clear table
Load from code
Build
Indent:
Select
Key
Value
Type
String
Number
Boolean
Null
Object/Array


Your profile is almost done! If you want to exhibit now, then touch the period. Otherwise you can save your data. I'll keep it safely what you gave.
Exhibition Period


RPSLS
Rock Paper Scissors Lizards Spock
rock
paper
scissors
lizard
spock
PICK YOUR CHOICE OF WEAPON AND SEE IF YOU WIN


This is text in a paragraph! Paragraphs are block elements, whereas span is an inline-element. Imagine a block as a box, whereas an inline-element like a plastic bag - we can build various structures by putting a box on a box, whereas plastic bags either wrap-up content or sit next to each other. Best way to figure out how they work is to play around with them!
Let's talk about a few inline elements. I am putting them in a paragraph to ensure that they are in a structured place rather than running around the website. You can quickly notice that inline elements are displayed next to each other, rather than below each other (like blocks). For example, this is a link to Google! and this is an image:
| Heading row - 1st column | Heading row - 2nd column |
|---|---|
| 2nd row - 1st column | 2nd row - 2st column |
| 3nd row - 1st column | 3nd row - 2st column |


Calculates the value of the expression between the opening and closing tag. Allowed characters are opening parenthesis ((),
closing parenthesis ()), pipe (|), plus sign(+), minus sign (-), multiplication operator (*), division operator (/), dot (.)
and percent sign (%), in addition to numbers and blanks, of course. Other characters in the expression are deleted.
2 * (3 + 5)
The result here is 16, which is printed, unless the calc-tag is used inside an assignment or something similar.


French
2 relevant subentries:
show all 2 leading
s
ຄິດຕະສັກກະຣາດ
kʰīt ---
1
noun
Christian era; A.D.
s
ຄິດຕະສາສນິກກະຊົນ
kʰīt ---
1
adjective
Christian.
s
ຄິດ
kʰīt
1
to comb/to comb oneself, to scratch/to scratch oneself
s
ຄິດ
kʰīt
1
(see) ຄຶດ 1), 2), 4);
2
to count, to compute, to calculate
3
to fix, to establish (a price, tax, etc.)
s
ຄິດ
kʰīt
1
to strain/pull tendons/ligaments
s
ຄິດ
kʰīt
1
Christ
English
Miscellaneous entries are shown below.
In some cases these have not yet been marked as (or tied to) headwords.
s
ຄຸ່ນຄິດ
kʰūn kʰīt
1
verb
preoccupy oneself with.
s
ຄູ່ຄິດ
kʰūː kʰīt
1
noun
associate, accomplice.
s
ຄົບຄິດ
kʰōp kʰīt
1
verb
conspire, act in concert; project; meditate.
s
ດັ່ງຄິດ
dāŋ kʰīt
ດັ່ງ ຄິດໄວ້
1
adverb
as thought.
s
ນຶກຄິດ
nɨ̄k kʰīt
1
verb
think, reflect on.
s
ຣິຄິດ
rī kʰīt
1
verb
initiate.
s
ວາຽຄິດ
wáːy kʰīt
1
verb
cease thinking or worrying about.
s
ສີ້ນຄິດ
sȉn kʰīt
1
verb
be at the end of one's wits.
s
ສຸດຄິດ
sút kʰīt
1
adverb
at one's wit's end; at a loss.
2
adjective
indecisive.
s
ສົມຄິດ
sŏːm kʰīt
ສົມ ຄຶດ
1
adverb
as hoped or desired; as foreseen
s
ອອກຄວາມຄິດ
ɔ̏ːk kʰẃam kʰīt
1
verb
express an opinion.
s
ຮູ້ຄິດ
hȗː kʰīt
1
adjective
well-considered.
s
ຮ່ວມຄິດ
hūaːm kʰīt
1
verb
think together, join one's thoughts.


Table filters are a series of go-pill
components used to show that the data within a table has been filtered.
In the table you can provide a series of these via content projection.
The table itself does not provide filtering capabilities, but provides a slot for these filters to live.


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Translator: qy-yang
This article will answer two questions:
What exactly is called “optimal substructure” and what is the relationship with dynamic programming?
Why does dynamic programming have various ways to traverse dp
arrays, some are traversing fowards,
some are traversing backwards, and some are traversing diagonally.
“Optimal substructure” is a specific property of some problems and is not exclusive to dynamic programming. In other words, many problems actually have optimal substructures, but most of them do not have overlapping subproblems, so we cannot classify them dynamic programming problems.
Here is a trivial example: supposed your school has 10 classes, and you have already calculated the highest test score for each class. So if I ask you to calculate the highest grade in the school, how would you do it? Obviously, it is not necessary to re-traverse the scores of all the students’. You only need to take the maxium score among the 10x highest (from each class).
This example exhibits optimal substructure: the optimal solution of a problem can be derived from the optimal solultions of subproblems. Calculating the highest score of each class is the subproblem. Once you know the answers to all the subprbolems, you can use this to derive the solution of the original problem which calculating the highest score across the school.
Although this problem has optimal-substructure property, it cannot be solved by dynamic programming due to lack of overlapping-subproblem property.
Here is an another example: Supposed your school has 10 classes, and you have known the maximum score difference (the difference between the highest score and lowest score) of each class. And now you want to calculate the maximum score difference among the students in the school, how would you do it? You should note that it can’t be calculated by taking the maximum score difference of these 10 classes. As the maximum score difference of the 10 classes does not necessarily result in the maximum score difference of the entire school. More concretely, the maximum score difference of the school may be the derived by the highest score of class 3 and the lowest score of class 6.
This problem does not exhibit optimal substructure, you cannot get the optimal solution of school through optimal solutions of each class. As mentioned in Detailed Explanation of Dynamic Programming, the subproblems must be independent of each other to satisfy the optimal-substructure requirement. In this example, the maximum score difference of the whole school may be derived from two classes. In other words, the subproblems are not independent, so this problem does not have the optimal substructure.
So what should be done when it lacks of optimal substructure? The trick is: recontructing the problem. For the problem of maximum score difference, as we can’t use score differences of each class, we can write a piece of brute-force code like this:
int result = 0;
for (Student a : school) {
for (Student b : school) {
if (a is b) continue;
result = max(result, |a.score - b.score|);
}
}
return result;
Next we can transform it to an equivalent problem and we should realise that: the maximum score difference is equivalent to the difference between the highest score and the lowest score; the highest and lowest score is required. So it is back to first question that has optimal substructure, and we can apply the optimal substructure to solve the highest-score & lowest-score problem, then solve the problem of maximum score difference. This is more efficient, isn’t?
The examples above are quite simple, but readers should notice that we are constantly seeking the maximum/minimum values for dynamic programming problems. This is exactly the same with the examples. Once again, dynamic programming is nothing more than solving the overlapping subproblems.
Previous sections “different definitions with different solutions” and “throwing eggs in high building throwing (advanced)” showed readers on how to transform the problem. Reader should understant that different optimal substructures may lead to different solutions and efficiency.
Here is another common and simple example: find the maximum value of a binary tree (for simplicity, assume that all the values in the nodes are non-negative):
int maxVal(TreeNode
root) {
if (root == null)
return -1;
int left = maxVal(root.left);
int right = maxVal(root.right);
return max(root.val, left, right);
}
Reader can observe that this problem also exhibits optimal substructure. The maximum value of the tree rooted at “root” node can be calculated from the maximum value of the subtrees (subproblem) at left side and right side. This is similar to the example of the highest score in school before.
The tree example above is not a dynamic programming problem. And readers should notice that the optimal-substructure property is not unique for dynamic programming. Most of the problems with optimal values have this property. However, the optimal substructure is a necessary condition for dynamic programming problems. So in the future, if you encounter the problem of optimal value. The dynamic programming is one of the right idea. This is the trick.
Dynamic programming is to induce the optimal solution starting from trivial base case. And it can be viewed as a chain reaction. Only the problems with optimal substructure have the chain reaction.
The process of finding the optimal substructure is actually the process of verifying correctness of state transition equation. There exists a brute-force solution, if the state transition exhibits the optimal substructure. Next is to check if there are overlapping subproblems. If so, some optimization can be done. This is another trick.
We are not giving the examples of non-classical dynamic programming here. Readers can read more about how state transition follows the optimal substructure from previous articles. Next, let ’s look at another confusing issue with dynamic programming.
dp
arrayI believe that some readers will definitely be confused with the traversal orders of dp
arrays when
doing dynamic programming problems . Taking a two-dimensional dp
array as an example, sometimes we
traverse forward:
int[][] dp = new int[m][n];
for (int i = 0; i < m; i++)
for (int j = 0; j < n; j++)
// Calculate dp[i][j]
sometimes we traverse backward:
and sometimes it may traverse diagonally:
// Traverse the array diagonally
for (int l = 2; l <= n; l++) {
for (int i = 0; i <= n - l; i++) {
int j = l + i - 1;
// Calculate dp[i][j]
}
}
Even more confusing, a correct answer can be obtained by traversing either forward or backward sometimes. For example, we can do both forward and backward in some parts of the problem “best time to buy and sell stock”.
If you look it closely, you should find out the reason. There are two rules you should take note:
1. During traversal, all the required states must have been calculated.
2. The final point of the traversal must be the point where the result is stored.
Let’s explain the two principles in detail.
For example, the classic problem “edit distance” that explained in the previous article Edit
Distance, by definition of dp
, we know that the base case is dp[..][0]
and
dp[0][..]
; and the final answer is dp[m][n]
. We also know from the state transition
equation that dp[i][j]
is derived from dp[i-1][j]
, dp[i] [j-1]
,
dp [i-1] [j-1]
, as shown below:
So, referring to the two principles, how would you traverse the dp
array? It should be a forward
traversal:
for (int i = 1; i < m; i++)
for (int j = 1; j < n; j++)
// First calculate dp[i-1][j], dp[i][j-1], dp[i-1][j-1]
// Then calculate dp[i][j]
In this way, the left, top, and top left of each iteration will be either base cases or states calculated before,
and finally it will end up with the answer we want dp[m][n]
.
Another example, the palindrome subsequence problem, refer to Strategies
For Subsequence Problem for details, from the definition of dp
array, we know the base case is in
the middle of diagonal of the array. dp[i][j]
is derived from dp[i+1][j]
,
dp[i][j-1]
, and dp[i+1][j-1]
, and the final answer to be calculated is
dp[0][n-1]
, as shown below:
In this case, there are two correct traversal orders:
Either traverse obliquely from left to right, or traverse from bottom to top, left to right, so that to ensure the
left, bottom, and bottom left of dp[i][j]
have been calculated.
Now, readers should understand these two principles, which are mainly dependent on the base case and the location of final result. Just to ensure that the intermediate results used during traversal have been calculated. There are multiple ways to get the correct answer sometimes, and readers can choose one based on your preference.


#include <authorizer.hpp>
| mesos::ObjectApprover::Object::Object |
( |
| ) |
|
|
inline |
| mesos::ObjectApprover::Object::Object |
( |
const authorization::Object & |
object | ) |
|
|
inline |
| const CommandInfo* mesos::ObjectApprover::Object::command_info |
| const ExecutorInfo* mesos::ObjectApprover::Object::executor_info |
| const FrameworkInfo* mesos::ObjectApprover::Object::framework_info |
| const quota::QuotaInfo* mesos::ObjectApprover::Object::quota_info |
| const Resource* mesos::ObjectApprover::Object::resource |
| const Task* mesos::ObjectApprover::Object::task |
| const TaskInfo* mesos::ObjectApprover::Object::task_info |
| const std::string* mesos::ObjectApprover::Object::value |
| const WeightInfo* mesos::ObjectApprover::Object::weight_info |
The documentation for this struct was generated from the following file:


This is prototype to a unit test to verify implementation of mash computation is correct, by comparing it to univariate case when $Y$ has one column and prior covariance matrices is fixed.
set.seed(1)
n = 1000
p = 1000
beta = rep(0,p)
beta[1:4] = 1
X = matrix(rnorm(n*p),nrow=n,ncol=p)
y = X %*% beta + rnorm(n)
#' res =susie(X,y,L=10)
library(mmbr)
prior_var = 0.2 * as.numeric(var(y))
residual_var = as.numeric(var(y))
data = mmbr:::DenseData$new(X,y)
residual_var
prior_var
m1 = mmbr:::BayesianSimpleRegression$new(ncol(X), residual_var, prior_var)
m1$fit(data, save_summary_stats = T)
head(m1$posterior_b1)
m1
# Assuming 1 out of $J$ are causal, we place a null weight $1-1/J$ a priori.
# This will lead to some shrinkage
# null_weight = 1 - 1 / ncol(X)
null_weight = 0
prior_covar = mmbr:::MashInitializer$new(list(0.2 * cov(y)), 1, prior_weights=1 - null_weight, null_weight=null_weight, alpha = 0)
residual_covar = cov(y)
prior_covar$prior_variance
residual_covar
m2 = mmbr:::MashRegression$new(ncol(X), residual_covar, prior_covar)
m2$fit(data, save_summary_stats = T)
head(m2$posterior_b1)
m2
All quantities seem to agree now.
ASH works well.
library(ashr)
a.out = ash(as.vector(m1$bhat), as.vector(m1$sbhat), mixcompdist = 'normal')
head(get_pm(a.out))
prior_covar$mash_prior
library(mashr)
data = mash_set_data(m2$bhat, m2$sbhat)
m.c = mash(data, g = prior_covar$mash_prior, fixg = TRUE, algorithm ='Rcpp')
head(get_pm(m.c))
Very similiar results to what I got with fixed g
earlier.
U.c = cov_canonical(data)
print(names(U.c))
m.c = mash(data, U.c, , algorithm ='Rcpp')
head(get_pm(m.c))
m.c$fitted_g


Computation times#
36:08.876 total execution time for auto_examples files:
Fingers flexion decoding on BCIC IV 4 ECoG Dataset ( |
09:18.620 |
1886.5 MB |
How to train, test and tune your model ( |
04:58.273 |
831.9 MB |
Searching the best data augmentation on BCIC IV 2a Dataset ( |
04:41.885 |
769.7 MB |
Benchmarking preprocessing with parallelization and serialization ( |
03:38.712 |
405.2 MB |
Hyperparameter tuning with scikit-learn ( |
03:13.743 |
497.9 MB |
Self-supervised learning on EEG with relative positioning ( |
02:11.091 |
147.5 MB |
Cropped Decoding on BCIC IV 2a Dataset ( |
02:08.980 |
861.8 MB |
Sleep staging on the Sleep Physionet dataset using U-Sleep network ( |
02:06.083 |
18.7 MB |
Data Augmentation on BCIC IV 2a Dataset ( |
00:54.073 |
1107.9 MB |
Trialwise Decoding on BCIC IV 2a Dataset ( |
00:53.823 |
724.4 MB |
Sleep staging on the Sleep Physionet dataset using Chambon2018 network ( |
00:41.542 |
8.5 MB |
Fingers flexion cropped decoding on BCIC IV 4 ECoG Dataset ( |
00:32.509 |
1057.5 MB |
Sleep staging on the Sleep Physionet dataset using Eldele2021 ( |
00:18.680 |
16.4 MB |
MOABB Dataset Example ( |
00:10.808 |
135.9 MB |
Load and save dataset example ( |
00:05.956 |
409.4 MB |
Split Dataset Example ( |
00:04.739 |
373.7 MB |
Process a big data EEG resource (TUH EEG Corpus) ( |
00:02.734 |
8.5 MB |
Custom Dataset Example ( |
00:01.913 |
8.5 MB |
Multiple discrete targets with the TUH EEG Corpus ( |
00:01.799 |
17.2 MB |
Regression example on fake data ( |
00:01.478 |
17.1 MB |
MNE Dataset Example ( |
00:01.435 |
8.6 MB |
Benchmarking eager and lazy loading ( |
00:00.000 |
0.0 MB |


c
0
ders
Website under development. Check back soon for more information. Meanwhile, contact us directly at
contact@c0ders.com


{% extends "FSJ/base.html" %} {% load i18n %} {% block heading %} {# Translators: Register page header #} {% trans "Register" %} {% endblock %} {# This page is displayed when an already active account attempts to register again. #} {% block content %}
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I'm a Brazilian self-taught Software Engineer, currently studying a lot about Pentesting, Cryptography, and Cloud Security. ~ (As a sidenote, I lean more towards the blue side, because incident handling and forensics are my favorites subjects by far)
My programming languages of choice are C++ (My favorite language), Python, and Javascript depending on what I'm working on. C++ mainly to develop desktop applications(Qt, OpenGL and Vulkan). Python for Cybersecurity(Scripting) and Data Science(Tensorflow, PyTorch). Javascript for Web Dev(Node, Angular, Express, and React/Redux) and Mobile(React Native).
I have a working knowledge of SQL, git, Bash, HTML, CSS(Bootstrap and Sass included), MongoDB, Postgres, and MySQL. I have studied other programming languages in the past, such as Pascal(My first language), Object Pascal, Visual Basic, Java, C and PHP, however I'm quite rusty in them nowadays.
I'm going to start posting in this blog at least once a week very soon. I just need to sort some stuff out before I start this commitment. There will be posts about web development, C++, cybersecurity, data science, cryptography and more!
If my skill set interests you, feel free to get in touch so maybe I can work with you and your team! (Remote work only)
Email me


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[gecode-users] Advisor: Delta Modification
Max Ostrowski
ostrowsk at cs.uni-potsdam.de
Fri Aug 31 13:27:05 CEST 2012
Hi everybody,
in case of the modification event Gecode::Int::ME_INT_VAL
i want to know what is the meaning of the IntView::min(d) and max(d)
methods (d==delta)
In the case of ME_INT_BND,
min(d)..max(d) is the range that was removed from the domain.
In the case of ME_INT_VAL
i sometimes have it being a removed range,
but sometimes it is min(d)=1 and max(d)=0.
I thought that this means that the domain was restricted on both sides
of the variable,
eg. x==6 while it was x = [1..10] before.
But this does not seem to be true in all cases.
So what is the meaning of these values.
Best,
Max
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Starting October 2018, Presidential Innovation Fellows (PIF) kicked-off and will lead a 14-week tech sprint with the U.S. Department of Health and Human Services (HHS) and other digital enthusiasts.
The goal of this tech sprint is to transform federal open data from HHS, the U.S. Department of Veterans Affairs (VA), and other agencies into digital tools. Modeled after The Opportunity Project (TOP) at U.S. Department of Commerce, the TOP Health tech sprint is specifically designed to improve the patient experience, for example, by assisting in novel therapeutics accessibility and improving clinical trials.
Presidential Innovation Fellows will lead a cohort of tech teams that are developing an ecosystem that leverages artificial intelligence (AI) technologies to help patients find new types of treatments. Several unique aspects of this tech sprint include cross-agency participation to create an ecosystem around a specific challenge, AI-centric data design, iteratively released data for training and testing, health-specific cohort, and access to specialized resources to foster a new AI-centric ecosystem. As part of this process, several industry partners have been chosen to participate
Github repository/data/code will be made available and updated here
The data is encoded using NCIt where possible (with mappings possible to others, such as SNOMED, etc.).
For the data set 1 (eligibility data) format, an example is for HIV
For data set 2 (participant data) format, please see dataset2_example_participant_format.xlsx.
For data set 3 (clinician-based match) data, please see dataset3_example_match_format.xlsx.


Please help to share the Knowledge >>
Water -
Studies at MIT laboratories and other independent research institutes shows that
a HHO gas enhanced engine can work at ultra lean regime with increased combustion
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horse-
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You will learn how to use HHO gas to reduce fuel consumption and pollution and how to properly tune the car to work with those changes.
The site includes complete plans of the hho generator: 3D model of the device, drawing kit of all parts and complete instructions of how to construct the cell and tune the car.
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Actually the HHO generator is “free 120 octane enhancer” to car’s fuel mixture.
Only small amount of hho gas is required to improve the combustion so with the correct electrolysis cell and proper fine tuning to the ignition system the additional load on the alternator is be minimal.
Before we begin: This information is not for everyone, only for open-
good luck.
The first step is to build the hydrogen gas saver.
You’re going to meet the First Aid HHO Cell
from the inside. Comprehensive explanation
about the device and how to build it including
drawings and 3D pictures.
This device produces a lot of hydrogen/oxygen gas on low amperage and even make you save fuel when not connected to power supply!
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Constructing the hho booster is only the first step in the right direction, but without a proper tuning to the car the whole concept is worthless. Tuning the car’s injection system or the carburetor is our next mission.
In order to really start saving fuel we need to make the car to work in ultra-
if we just increase the amount of air in the mixture the engine will run hotter, but if we replace some of the air with Hydrogen/Oxygen mixture from the booster the running temperature will actually go down while the engine converting more chemical energy into motion instead of heat...
Proper tuning to the car is as important as the hydrogen device itself.
We Saved noting to ourselves, Gives you everything you need to know about hho cell. Plans include Mechanical Drawings accurate up to the mm. The Plans include not only the hho generator itself but also how to connect it and fine tune all the details.
For people who want to get into hho buisness really fast you can consider to get an hho generator “off the shelf”. This option fits to people don’t want to waste time and want to get hho device of a proven quality.
You can find high quality hho generator here:
These guys sell full hho kit including all the parts.
While my recommendation is to build hho kit for
Yourself , you can get one here really fast.


Kremlin confirms Putin to take part in Ukrainian peace summit in Paris
MOSCOW (Reuters) - The Kremlin confirmed on Monday that Russian President Vladimir Putin would take part in a four-way international summit in Paris on Dec. 9, an attempt to advance efforts for a peaceful resolution to the conflict in eastern Ukraine.
The French presidency said on Friday that the leaders of France, Germany, Russia and Ukraine would take part. But until Monday the Kremlin had failed to publicly confirm its attendance.
Kremlin spokesman Dmitry Peskov told reporters on Monday that Putin would attend, but declined to discuss what Moscow’s expectations for the event were.