MySQL Magazine: Summer 2008 (Issue #5)

8/14/2019 MySQL Magazine: Summer 2008 (Issue #5)

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2 SQLYog Enterprise Edition Version 6.55 Review

10 Ma'atkit Toolkit Tutorial: mk-table-checksum

13 Command Line mysql Client Options

21 MySQL Magazines 2008 Annual Usage Survey

Summer 2008

I s sue 5

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6 Coding Corner

22 news

42 log-bin

News, articles and feedback for MySQL database administrators and developersusing MySQL on a daily basis to provide some of the best database infrastructure available.


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Page 2 Summer 2008 MySQL Magazine

This software is one of the most popular GUI-based tools for MySQL. Most of the features of the software

are geared to help the daily work of DBAs and developers. The software is rich in features and therefore thisreview will only highlight some of the cool capabilities.

Connection to Remote Servers

SQLYog Enterprise Edition Version 6.55 Review

One nice thing about this software

is that you can easily scan your

database for information. Here is a

quick example. Let's say that you

have several tables in a database with

multiple columns, and you want to

query your database. If you are using

the command line, you would

probably use the following: show

tables status, show fields, show

create table, and show keys.

SQLyog gives you the ability to

see your table information as soon as

Most companies require you to use the ssh

protocol to access their servers. While it is easy to

setup your own ssh tunnel to connect to your

remote database, it is quite cumbersome to do that.

SQLYog allows you to easily do this and lets you save

your secure MySQL connection. I use this all the time

and I do not even think about ssh tunnelinganymore.

On the downside, when I tried to connect to

another database, the software opened a separate

window for me. This made it difficult for me to

switch from one window to another. This can be

annoying if you want to compare two databases but

it could also be a security measure so that you do

SQLYog Reviewcontinues on next page

By Jonathan Cua

not accidentally apply the wrong SQL statements to the wrong database.

Scanning Table StructuresIf you want to find out the structure of a table, you typically have to type several commands from the

MySQL command line. Certainly there is nothing difficult about this, but if you are going to do this for several

tables then it becomes somewhat annoying.


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you connect to your database. When you click on a table you immediately see the table definition, indexe

and columns associated with it. SQLyog actually runs all the above commands in the background so that i

can quickly show you the table structure at once.

You can imagine the time that you can save without typing all of the above commands. Also, when yo

are trying to write your SQL logic, you can ignore the needing to issue a show fields command in order toget the proper spelling of a column.

Multiple Ways to Create SQL QueriesThere are two ways to create queries in SQLyog.

1. T1. T1. T1. TYPE THE QUERY IN A QYPE THE QUERY IN A QYPE THE QUERY IN A QYPE THE QUERY IN A QUERY TAB WINDOW WITHUERY TAB WINDOW WITHUERY TAB WINDOW WITHUERY TAB WINDOW WITH THE AID OF AUTOTHE AID OF AUTOTHE AID OF AUTOTHE AID OF AUTO----COMPLETE ANDCOMPLETE ANDCOMPLETE ANDCOMPLETE AND SQLSQLSQLSQL SYNTAX TEMPLATESYNTAX TEMPLATESYNTAX TEMPLATESYNTAX TEMPLATE....

where you can simply insert SQL templates that give you the proper syntax ready for use.

2. U2. U2. U2. USE THESE THESE THESE THE QQQQUERYUERYUERYUERY BBBBUILDER TO CREATE THEUILDER TO CREATE THEUILDER TO CREATE THEUILDER TO CREATE THE QUERYQUERYQUERYQUERY....

Unlike the MySQL command lin

where you have to type everythin

correctly (SQL code, column names, tabl

names) SQLyog helps you by providing a

auto-complete feature where you simplclick on the TAB button and it wi

complete the word that you are typing

This could be a SQL function, colum

name, or table name.

Also, how many times have yo

forgotten the syntax of a SQL comman

and you had to search for the prope

syntax of it? SQLyog has a built-in featur

This involves dragging

the table from the schema

objects to a blank window.

You can then join tables,

specify filters, group the

columns, and arrange the

sort order. The software

will build the equivalent

SQL command for you andall of this can be done

without typing a single

SQL code.

SQLYog Reviewfrom previous page



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the Windows scheduler to run backup and emails you of the result of the backup.

I tested this feature by letting the software save my backup scheduler configuration; the software stored

the information in an XML file where it contained my database username, database password, email address,

and email password all in plain text! I have tried to work around this problem but I could not find a way to

solve this.

Database and Structure Synchronization

SQLyog allows you to synchronize two different databases (both structure and data). It actually creates

the corresponding SQL commands so that if executed the two databases would become synchronized with

each other.

I tested this and I was satisfied with the SQL output of the software. It was able to synchronize two

different databases with little effort on my part. The tool has a wizard that will guide you step-by-step on

what to do. It was simply selecting which database and which tables to synchronize and it did its job.

I use this all the time when releasing new schema into production. This tool makes it easy to apply the

necessary SQL commands to make the production schema the same as the development schema.

Data ModelingSQLyog provides a visual schema designer where you can create your tables, design the relationships and

it will automatically update your database. One nice thing about this feature is that when I want to see the

relationship of two or three tables I just drag them in the browser window and the software will show me the

visual relationship of the tables.

If you are building an Entity Relationship Diagram (ERD) for a big database, then you would probably use

another software. But I find this feature of SQLyog quite handy as I do not have to rely on another software to

create a small ERD.

Database ManagementManaging the database is quite easy with this

software. I was able to create new tables, manage

indexes, add users and remove their permissions

without typing any SQL commands. It is all point and

click.

It also supports the following features: copying of

database to different hosts, creating duplicates of

tables, renaming of tables, re-ordering of the

columns, and changing the engine type of the

database. What made this easy is that the software will

guide you on what you have to do, so when you want

to create copies of your tables, it is simply a matter of

ust clicking on that option.

Backups with SQLyog were easy as well and I found

no difference between doing backups on SQLyog or

mysqldump. An additional feature is that SQLyog uses




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Migration ToolkitThis feature allows you to move non-MySQL data into your MySQL database. Just like the other features, i

has a wizard that will guide you on what you need to do. I have tried this feature a couple of times and i

seems to work just fine. I have not tested this on a large database and I do not know how the software wirespond to a larger dataset. Also, for a large database, I would probably do the migration in small steps such

as making sure that the old and new column definitions match, instead of doing everything in one big step

and finding out in the end that something was wrong in the beginning. So, I would be hesitant to completel

rely on this feature.

ConclusionThis software provides a nice tool for MySQL DBAs and developers. Although SQLyog does not provid

anything unique in terms of features (there are equivalent scripts or tools out there that will do the same job)

SQLyog attempt to provide an all-in-one solution. For more information, please visit the website

http://www.webyog.com.

About the AuthorJonathan Cua is a senior database administrator with over 10 years of experience in open source

technology, large databases and data management systems.



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C o d i n g

o

rn

e

r

By Peter Brawleyhttp://www.artfulsoftware.com

Here is a case in point. Some firms motivate their sales forces with graduated sales commissionslike thegraduated income tax, but in the salespersons favor. Calculation of these commissions is stepwise, range by

range. Every computer-savvy bookkeeper on the planet knows how to do this in a spreadsheet. How is it done

in MySQL?

For an example assume the following tables for employee sales and commission rates:

Divide and ConquerA MySQL query might call up hundreds of data columns

and millions of data rows, but it will use seven basic

operations at mostselection,join, restriction, aggregation,division, union, and logical branching.

Then why are so many queries hard to write? Call it the

craftsmans dilemma. The set of tools is small and the rules

for using them are few, but problems come in unlimited

size, variety, complexity and disguise. As Kurt Gdel proved,

no algorithm can capture all the possibilities. To get better

at writing queries is to get better at the most famous

problem-solving meta-method in the world: divide and

conquer.

DROP TABLE IF EXISTS sales, comms;CREATE TABLE sales(employeeID int,sales decimal(10,2));

INSERT INTO tblsales VALUES(1,2000),(1,5000),(1,7000),(2,9000),(2,15000),(2,12000);SELECT * FROM tblsales;+------------+----------+| employeeID | sales |+------------+----------+| 1 | 2000.00 || 1 | 5000.00 || 1 | 7000.00 || 2 | 9000.00 || 2 | 15000.00 || 2 | 12000.00 |+------------+----------+CREATE TABLE comms(

commstart DECIMAL(10,2),commend DECIMAL(10,2),pct INT

);

INSERT INTO comms VALUES(0,10000,5), (10000,20000,10), (20000,30000,15),(30000,40000,20), (40000,50000,25), (50000,60000,30);

Divide and Conquercontinues on next page


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SELECT * FROM comms;+-----------+----------+-----+| commstart | commend | pct |+-----------+----------+-----+

| 0.00 | 10000.00 | 5 || 10000.00 | 20000.00 | 10 || 20000.00 | 30000.00 | 15 || 30000.00 | 40000.00 | 20 || 40000.00 | 50000.00 | 25 || 50000.00 | 60000.00 | 30 |+-----------+----------+-----+

One atom of this problem molecule is how to apply one commission range (commstart to commend) to

one sales amount (amt). There are three cases to cover:

1. if amt < commstart, base amount = 0

2. if amt commend, base amount = commend - commstart

It is basic branching logic:

IF( s.amt < c.commstart,

0,

IF( s.amt


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How do we plug the formula into the join? Add the formula to the SELECT list twicefor base amount and

for commission:SELECTs.employeeID ID, s.amt, c.commstart start, c.commend end,

IF( s.amt


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Pa e 10 Summer 2008 M SQL

Maatkit Toolkit Tutorial: mk-table-checksum

Most production environments have a master/slave setup of servers. This provides the ability to easily

perform backups, have warm fail-over if you have a hardware failure on the master, etc. Replication between

the master and slave is fairly easy to set up, however as Baron Schwartz points out here:

http://www.xaprb.com/blog/2007/11/08/how-mysql-replication-got-out-of-sync/ it is possible (and

probably quite common) for a master

and slave to drift out of sync.

Fortunately, not only did he point out

the problem, he provides a fix for the

problem. Included in the maatkit toolkit

(http://maatkit.sf.net) is the mk-table-

checksum tool (and the related tool mk-

table-sync which we wont be discussingin this tutorial). It can tell you which

tables on the master and and slave are

out of sync and even tell you within a

fair degree what rows are out of sync.

Here is an example run:

mk-table-checksum chunksize 500000 replicate=test.checksum localhost

What are we doing here? Well, the chunksize option specifies that if tables are larger than 500,000 rows (in

this case) that they should be chunked broken apart when processing. This will mean that a table

doesnt get blocked for too long a period of time. The replicate option specifies that you are wanting the

checksum tool to use the test.checksum table to store results in. This can be very helpful in providing an

accurate picture of your results. The create command for this table should be:

CREATE TABLE `checksum` (`db` char(64) NOT NULL,`tbl` char(64) NOT NULL,`chunk` int(11) NOT NULL,`boundaries` char(64) NOT NULL,`this_crc` char(40) NOT NULL,`this_cnt` int(11) NOT NULL,

`master_crc` char(40) default NULL,`master_cnt` int(11) default NULL,`ts` timestamp NOT NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,PRIMARY KEY (`db`,`tbl`,`chunk`)) ENGINE=InnoDB DEFAULT CHARSET=latin1;

It doesnt have to be in the test database by the way. You can put it wherever you want. Your option. Just be

sure to specify the right database when running the mk-table-sync command.

The final option is really easy. It just specifies the location of the master server. In this case, I ran the

command on the master server itself so localhost was specified.

mk-table-checksumcontinues on next page

By Keith Murphy

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For free?

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MySQL University is in session!

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Page 11 Summer 2008 MySQL

mk-table-checksumcontinued from previous page

It will take a while for this command to run if your databases are of a significant size. Once it is done

executing and your slave has caught up (if it lagged behind the master) then you just run the following:

mk-table-checksum replicate=test.checksum replcheck 2 localhost

This will give you the results you want. Here is some sample output:

mk-table-checksum --replicate=test.checksum replcheck 2 localhost

Differences on h=server.slaveDB TBL CHUNK CNT_DIFF CRC_DIFF BOUNDARIESdatabase_1 table_1 0 0 1 `clientid` < 184723database_1 table_2 0 0 1 `clientid` < 184721mysql db 0 -19 1 1=1mysql user 0 -1 1 1=1

This shows that there were some differences on the slave. In the mysql database, on the slave, there ar

nineteen fewer rows in the db table and one less row in the user database. This is because I have differen

permissions on my master and slave servers.

On database_1 I have two tables that are out of sync. The two table_1 tables (on the master and slave) have

the same row count (shown by the cnt_diffcnt_diffcnt_diffcnt_diff column). However, the crc_diffcrc_diffcrc_diffcrc_diff column shows that there ar

differences in the contents of the columns on the two tables. The boundariesboundariesboundariesboundaries column show you which chun

of the table that the differences are located in. You can use this to figure out the exact problem yourself.o

you can use the mk-table-sync tool to do this for you.

There is a custom udf (user defined function) that Baron Schwartz programmed for use in the maatki

toolkit. Essentially the udf provides a replacement for the md5 hash function in MySQL. This custom function

provides an impressive speedup. On two servers I ran the mk-table-checksum tool with the default setup and

then installed the udf and re-ran the checksum tool. Here are the results:

server checksum w/md5 checksum w/fvn

db3 17m10.220s 5m0.090s

db6 112m21.719s 53m58.368s

Clearly it is a great benefit to use this udf if you are running table checksums. So how do you set it up? The

source code is included in the tar.gz file that is distributed from the maatkit website. Just download an

unzip/untar. In the included files there is a udf directory with one file. To compile just:

gcc -fPIC -Wall -I/usr/include/mysql -shared -o fnv_udf.so fnv_udf.cc

The instructions are included in the source code. Once you have it compiled, just copy the resultant fil

(fnv_udf.so) to the /lib directory and then run the command:

mysql mysql -e CREATE FUNCTION fnv_64 RETURNS INTEGER SONAME fnv_udf.so

mk-table-checksumcontinues on next pag


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This adds the function to your MySQL server setup. To test, log into mysql and make this call:

mysql> SELECT FNV_64(hello, world);

This should returns some results if everything is done properly. Once your MySQL server sees the new

udf maatkit will begin using it automatically.

Baron has an excellent background post on the fvn udf here:

http://www.xaprb.com/blog/2008/03/09/a-very-fast-fnv-hash-function-for-mysql

About the authorKeith Murphy is a MySQL database administrator for The Pythian Group. He is also the editor of MySQL

Magazine.The views and opinions expressed in this article are the authors own and may not reflect the views and

opinions of The Pythian Group.

mk-table-checksumcontinued from previous page

Are You Forging?

The MySQL Forge is the premier place for code, tools,

software previews, worklogs, and projects by and for theMySQL community.

Visit http://forge.mysql.com/ to see whats being forged!


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Command Line mysql Client OptionsBy Sheeri K. Cabral

The most commonly used options for the mysql command line client are the connectivity options. These

options are boring because they do not improve your experience with the command line client:

Table 1, Connectivity Options to MySQL

OptionOptionOptionOption Long Option NameLong Option NameLong Option NameLong Option Name DescriptionDescriptionDescriptionDescription ExampleExampleExampleExample

-u uname --user=uname Specify username -u sheeri--user=webuser

-h host --host=host Specify database server; host can be a

short hostname, a fully qualified domain

name (FQDN) or an IP address.

-h 192.168.1.100--host=foo.bar.com

-p

-ppass

--password=pass Enclose pass in quotes if it has special

characters. If no password specifed, askfor password interactively.

-p-psecret

--password='foo!'

-P portnum --port=portnum Specify port -P 3307--port=3308

-S file --socket=file Specify socket; file can be a relative or

absolute path to the socket

-S /tmp/mysql.sock--socket=my.sock

The mysql client has many other useful options. Some options are similar to commands that can be run in

the interactive mysql shell. Others provide ways to change the formatting of the output, improve you

interactive and batch processing experiences, and change how the mysql client uses memory.

When thinking of the mysql command line client, you probably think of the interactive shell:

Welcome to the MySQL monitor. Commands end with ; or \g.Your MySQL connection id is 687673Server version: 5.0.45-community-nt-log MySQL Community Edition (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql>

However, the mysql command line client can also be used to process a batch of queries.

Batch OptionsThe -execute option (short name -e) will process a batch list of one or more queries, provided on

command line:shell> mysql -u root -prootpass --execute="SHOW DATABASES;"+--------------------+| Database |+--------------------+| information_schema || mysql || sakila || test |+--------------------+

mysql optionscontinues on next pag


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mysql optionscontinued from previous page

shell> mysql -u root -prootpass -e "SHOW DATABASES; USE mysql; SHOW TABLES LIKE 'user';"+--------------------+| Database |+--------------------+| information_schema || mysql || sakila || test |+--------------------++------------------------+| Tables_in_mysql (user) |+------------------------+| user |+------------------------+

shell>

You can also run a batch commands by redirecting SQL commands to the mysql command line client tool.

This can be done with pipes or using the redirection operator.

shell> echo SHOW DATABASES | mysql -u root -prootpassDatabaseinformation_schemamysqlsakilatest

shell> echo SHOW DATABASES; >> batch.sql && echo USE mysql; >> batch.sql && echo SHOWTABLES LIKE 'USER'; >> batch.sql

shell> more batch.sql

SHOW DATABASES;USE mysql;SHOW TABLES LIKE 'USER';

shell> mysql -u root -prootpass < batch.sqlDatabaseinformation_schemamysqlsakilatestTables_in_mysql (USER)user

Notice that the output is formatted differently. This is because redirected commands act as if they were in

batch mode. The -B option (long format --batch) disables interactive mode and enables the --silent option.

The --silent option replaces the default table formatting of the output with tab-separated rows, each on a

new line. To get non-table formatting using the execute option, use either the -B or the --silent option:

shell>mysql -u root -prootpass -B --execute="SHOW DATABASES;"Databaseinformation_schemamysqlsakilatest

Note: All the examples in thisarticle have been designed and

tested to work on both Linux and

Windows; they will likely work on

Solaris and Mac OS X as well.

mysql optionscontinues on next page


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shell>mysql -u root -prootpass --silent -e "SHOW DATABASES;"Databaseinformation_schemamysqlsakilatest

If you want table-style formatting in batch mode, use the -t option (long format --table):

C:\Documents and Settings\Owner.TcationTreas>mysql

-u root -prootpass -t < batch.sql+--------------------+| Database |+--------------------+| information_schema || mysql || sakila || test |+--------------------+

+------------------------+| Tables_in_mysql (user) |+------------------------+| user |+------------------------+

Note that all of the options to mysql can be specified in

the [mysql] or [client] group of an option file, such as

/etc/my.cnf and ~/.my.cnf and my.ini. Simply use the long

name and omit the -- in front of the long name. So if you

want to disable table formatting all the time, simply put

silent in the [client] directive of a configuration file.

MySQL, MySQL logos and

the Sakila dolphin are

registered trademarks of

MySQL AB in the United

States, the European

Union and other countries.

MySQL Magazine is not

affiliated with MySQL AB,

and the content is not

endorsed, reviewed,

approved nor controlled

by MySQL AB.

Output OptionsIf you find yourself copying and pasting outpu

frequently, you probably curse MySQL's table-styl

formatting. The good news is that the --silent option

works with the interactive mysql command line as wel

Note that in silent mode, the usual MySQL heade

showing information like the version, connection ID and

welcome message are suppressed, as well as the Bye

message upon exit:

shell>mysql -u root -prootpass --silentmysql> SHOW DATABASES;Databaseinformation_schemamysqlsakilatestmysql> exit

shell>

Have a topic for afuture editionof

the MySQL Magazine? Sendarticles and ideas to:Keith Murphy, Editor

[email protected]

Download pDownload pDownload pDownload previous editionsrevious editionsrevious editionsrevious editions

of the MySQL Magazineof the MySQL Magazineof the MySQL Magazineof the MySQL Magazine at:at:at:at:

http://www.mysqlzine.nethttp://www.mysqlzine.nethttp://www.mysqlzine.nethttp://www.mysqlzine.net

andandandandhttp://paragonhttp://paragonhttp://paragonhttp://paragon----cs.com/mag/cs.com/mag/cs.com/mag/cs.com/mag/


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While using silent or table mode, it may be desirable not to have the column names printed. The --skip-

column-names option does just that:

shell> mysql -u root -prootpass --skip-column-names

Welcome to the MySQL monitor. Commands end with ; or \g.Your MySQL connection id is 21Server version: 5.0.45-community-nt-log MySQL Community Edition (GPL)


mysql> show databases;+--------------------+| information_schema || mysql || sakila || test |+--------------------+

4 rows in set (0.00 sec)

mysql> exitBye

shell>mysql -u root -prootpass --silent --skip-column-namesmysql> show databases;information_schemamysqlsakilatestmysql> exit

shell>The \G command in the interactive mysql command line shell is very useful when used at the end of a

query instead of ; or \g, it outputs a query in vertical format. The -E option (long format --vertical) makes the

output print vertically without having to use the \G command with every query. This vertical option can be

used interactively or in batch mode:shell> mysql -u root -prootpass --vertical mysql -e "SHOW TABLE STATUS LIKE 'user';*************************** 1. row ***************************Name: userEngine: MyISAMVersion: 10Row_format: DynamicRows: 2

Avg_row_length: 104Data_length: 312Max_data_length: 281474976710655Index_length: 2048Data_free: 104Auto_increment: NULLCreate_time: 2007-07-04 09:49:18Update_time: 2007-09-23 16:14:15Check_time: NULLCollation: utf8_binChecksum: NULLCreate_options:Comment: Users and global privilegesshell>




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If you want to have fancier output, the -H option (long format html) and -X option (long format xml) wil

output html and xml styles, respectively:

shell>mysql -u root -prootpass --html mysqlWelcome to the MySQL monitor. Commands end with ; or \g.Your MySQL connection id is 28Server version: 5.0.45-community-nt-log MySQL Community Edition (GPL)


mysql> show tables;Tables_in_mysqlcolumns_privdbfunchelp_categoryhelp_keywordhelp_relationhelp_topichostprocprocs_privtables_privtime_zonetime_zone_leap_secondtime_zone_name

time_zone_transitiontime_zone_transition_typeuser17 rows in set (0.00 sec)

mysql> exitBye

shell> mysql -u root -prootpass --xml -e "USE mysql; SHOW TABLE STATUS LIKE 'user';

userMyISAM10Dynamic210431228147497671065520481042007-07-04 09:49:182007-09-23 16:14:15

utf8_binUsers and global privileges


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Logging OutputYou may already know about the --tee and --disable-tee options, which are similar to the mysql

interactive commands tee and notee. --tee=name will append output into the outfile specified as well asdisplaying it on screen. This is similar to:

mysql> tee nameLogging to file 'name'

To stop writing to the outfile while in the interactive client shell, the notee command is used:

mysql> noteeOutfile disabled.

The equivalent option to mysql is --disable-tee will disable the outfile. Using --disable-tee still allows

for the tee and notee commands to be run in the interactive client shell. Thus, using --disable-tee only

makes sense if you want to override a --tee option specified in an option file.

Other OptionsAnother option that is similar to a command on the interactive command line is --prompt=name, similar to

the prompt command on the interactive command line. This sets the mysql prompt to name. The default is

mysql>. Diego Medina has a sample prompt on the MySQL Forge at:

http://forge.mysql.com/tools/tool.php?id=126

shell>mysql -u root -prootpass --prompt="mysql [\h] {\u} (\d) > "Welcome to the MySQL monitor. Commands end with ; or \g.Your MySQL connection id is 44Server version: 5.0.45-community-nt-log MySQL Community Edition (GPL)


mysql [localhost] {root} ((none)) > use mysql;Database changedmysql [localhost] {root} (mysql) >

\h, \u, and \d are special character sequences that refer to the host, username, and database, respectively.

A complete list of special character sequences to use with --prompt can be found at

http://dev.mysql.com/doc/refman/5.0/en/mysql-commands.html.

Another useful interactive option is --pager, which specifies the pager to use to display results. The most

common usage is --pager=more (or less), but you can also use any appropriate shell command:


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shell> mysql -u root -prootpass --pager="grep info"Welcome to the MySQL monitor. Commands end with ; or \g.Your MySQL connection id is 68Server version: 5.0.45-community-nt-log MySQL Community Edition (GPL)


mysql> show databases;| information_schema |4 rows in set (0.02 sec)

mysql> use information_schemaReading table information for completion of table and column namesYou can turn off this feature to get a quicker startup with -A

Database changed

mysql> show tables;| Tables_in_information_schema |16 rows in set (0.03 sec)

mysql>

Some folks find it annoying that MySQL will

display an error, but in order to see a warning you

have to type SHOW WARNINGS after noticing that a

warning was generated. You can set the --show-

warnings option to automatically print warning

statements just like error statements.

I will end with one of my favorite options to themysql command line client, --sigint-ignore. This

ignores the SIGINT command, otherwise known as

CTRL-C. CTRL-C means copy in many programs,

and I often hit CTRL-C after highlighting some text

because I mean to copy it. This sends a sigint or

break signal to the mysql server, which is not the

desired result. The --sigint-ignore option means

that I can hit CTRL-C to my heart's content and not

cause anything to happen. You will have to test this

on your own system, as it is difficult to show that akeystroke had no effect in an article.

For a complete listing of what your client can do,

use the --help option to mysql. As you might

expect, --help shows syntax and available options

for your version ofmysql. However, --help also

notes the order in which the applicable option files

are read, and which groups are applied:

Cant Get Enough?

If a quarterly dose of MySQL news andtechnical articles is not enough, visit PlanetMySQL at http://planetmysql.org to readthe MySQL employee and community blogs.There are several new articles daily;bloggers can submit feeds as well.

http://planetmysql.org


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shell> mysql --help | moremysql Ver 14.12 Distrib 5.0.16, for pc-linux-gnu (i386) using readline 5.0

Copyright (C) 2002 MySQL ABThis software comes with ABSOLUTELY NO WARRANTY. This is free software,and you are welcome to modify and redistribute it under the GPL licenseUsage: mysql [OPTIONS] [database]-?, --help Display this help and exit.-I, --help Synonym for -?......[more options deleted]......--show-warnings Show warnings after every statement.

Default options are read from the following files in the given order:/etc/mysql/my.cnf ~/.my.cnfThe following groups are read: mysql client

The last part of the output of --help is the default variable settings after the applicable configuration files

and groups are read:

Variables (--variable-name=value)and boolean options {FALSE|TRUE} Value (after reading options)--------------------------------- -----------------------------auto-rehash TRUEcharacter-sets-dir (No default value)default-character-set latin1compress FALSEdatabase (No default value)delimiter ;......[more default values deleted]......secure-auth FALSEshow-warnings FALSE

Hopefully this article has helped you be more productive using the command line mysql client.

About the authorSheeri K. Cabral is a MySQL DBA for The Pythian Group. She founded Technocation, Inc.

(www.technocation.org), a not-for-profit organization dedicated to providing free educational resources for

IT professionals. In her spare time, she fills Technocations site with videos from conferences and user

groups, blog postings, and occasionally podcasts. For all her volunteer work, Cabral won MySQLs

Community Advocate Award in 2007 and 2008.

The views and opinions expressed in this article are the authors own and may not reflect the views and

opinions of The Pythian Group.



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Surveycontinues on next pag

MySQL Magazine's 2008 Annual MySQL Usage Survey

By Keith Murphy

It has been my desire to do this survey for quite some time. With the help of Mark Schoonover wedeveloped thirty-four questions covering a range of subjects. There were over 400 responses to the survey

with people chiming in from all over the world. Because of space constraints I am not going to spend any

time giving analyses of the results here. In my log-bin column I manage to get in a few thoughts however.

Q1 Primary Job Function

0

20

40

60

80

100

120

140

160

180

48

4 6

59

59 7 8

159

60

9

Internet/Intranet/ExtranetManagement/Development/Strategy

E-BusinessManagement/Development/Strategy

E-CommerceManagement/Development/Strategy

New Media Manage-ment/Strategy

Webmaster/Web Devel-opment

Other E-Business/InternetManagement/Development/Strategy

IS/MIS/DP

Network SystemsDataCommunications/Telecommunications

Software/Applications De-velopment/Programming

SystemsEngineering/Analysis/Integration/Technical Services

Other


22/42


Surveycontinued from previous page

Q2 What country do you live in?

Survey continues on next page

AustraliaBrazil

BelgiumCanada

ChinaEurope

FinlandFrance

GermanyIndia

ItalyNetherlands

PeruPoland

RomaniaScotland

SerbiaSweden

UKUSA

South AmericaUkraine

0

5

10

15

20

25

30

6

1

3

7

3

1 1

2

3

2

4

2

1 1

2

1 1

8

4

27

2

1

NewsThis issue brings us a couple of announcements about major versions of software that can be used to

support MySQL. Monday, July the 14th, saw the release of SQLyog 7.0. We have a complete review of the

previous release in this very issue. New features of this release include:

New GRID design for easier navigation

Multiple selection in GRIDs with SHIFT+CLICK.

Improved Data Synchronization. Now typically 2-8 times faster than before depending on data.

Option to generate a SQL sync script was added.

Drastically improved the speed of exports.

New more user friendly design for the Schema Synchronization (renamed from Structure

Synchronization).

Added automatic and manual update check

In addition, one of our new advertisers, dbWatch Software, is opening a sales office in the United

States. Their product dbWatch (v8.1) is a heterogeneous database monitoring/reporting tool currently

supports Oracle, SQL Server, and MySQL.


23/42



Q3 Is your position local or remote?

0

50

100

150

200

250

300

350

310

80

Local ( I work in an office )

Remote

Q4 Years of MySQL Experience

0

20

40

60

80

100

120

140

160

46

121

136

70

19


24/42



Q5 Salary

0

5

10

15

20

25

30

35

30

15

20

12

27

12

17

13

20

17

24

16

19

24

1516

26

27

4

28

< $20,000

$20,000-$29,999

$30,000-$34,999

$35,000-$39,999

$40,000-$44,999

$45,000-$49,999

$50,000-$54,999

$55,000-$59,999

$60,000-$64,999

$65,000-$69,999

$70,000-$74,999

$75,000-$79,999

$80,000-$84,999

$85,000-$89,999

$90,000-$94,999

$95,000-$99,999

$100,000-$109,999

$110,000-$119,999

$120,000-$129,999

> $130,000

Surveycontinues on next page


25/42




Q6 Do you have additional duties?

0

50

100

150

200

250

300

214

108

272

26

System Administration

Network Administration

Programmer

Other


26/42




Q7 What is your organization's primary business activity?Online RetailerInternet Service Provider (ISP) or Applica-

tion Service Provider (ASP)

Communications Carrier

Aerospace

Banking/Finance/Accounting

Insurance/Real Estate/Legal

Federal Government (including military)

State/Local Government

Medical/Dental/Healthcare

Transportation/Utilities

Construction/Architecture/EngineeringData Processing Services

Wholesale/Retail/Distribution

Education

Marketing/Advertising/Entertainment

Research/Development Lab

Business Services/Constultant

Computer Manufacturer (Hardware,

software, peripherals)

Computer/Network Services/Consultant

Computer Related

Reailer/Wholesaler/Distributor

0

10

20

30

40

50

60

70

80

28

71

5

1

18

1

6 7

13

52

22

3

3836

10

19

28

65

1


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Q8 Do you have any MySQL Certifications?

0

50

100

150

200

250

300

350

400

343

1711 8

30

7

No

MySQL 4.x Base

MySQL 4.x Professional

Certified MySQL Associate(CMA)

Certified MySQL DatabaseAdministrator (CMDBA)

Certified MySQL ClusterAdministrator (CMCDBA)

Certified MySQL Developer(CMDEV)


28/42




Q9 If you do have MySQL Certification, how did you prepare for it?

0

10

20

30

40

50

60

70

80

67

2

10

35

Self Study

Conference TutorialMySQL Training Course

Company Internal MySQLTraining Course

Other


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Q10 Which MySQL Certification are you planning on obtaining this year?

0

50

100

150

200

250

300

350

288

13

41

18

39

None

Certified MySQL Associate(CMA)

Certified MySQL DatabaseAdministrator (CMDBA)

Certified MySQL ClusterAdministrator (CMCDBA)

Certified MySQL Developer(CMDEV)

Q11 What operating systems do you run MySQL on

Ubuntu

RedHat

CentOS

Slackware

Debian

Solaris SPARC

Solaris Intel

Windows 2000/2003

FreeBSD

MAC OS/X

Fedora

Other0

20

40

60

80

100

120

140

160

180

155

164

122

7

120

28 28

123

41

77

710


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Q12 What versions of MySQL do you use? (multiple choice)

0

50

100

150

200

250

300

350

22

164

313

206

16

MySQL 3.x

MySQL 4.x

MySQL 5.0.x

MySQL 5.1.x

MySQL 6.x

Q13 Do you work with other RDBS? (multiple choice)

No

Oracle

MSSQL

Sybase

PostgreSQL

DB2

SQLlite

Other0

20

40

60

80

100

120

140

160

137

106

101

22

99

9

27

19


31/42



Q14 Which MySQL high availability solution are you currently using? (multiple choice)

0

50

100

150

200

250

203

31

153

55

26

Q15 Have you or your company outsourced DBA duties?

0

50

100

150

200

250

300

350

400

34

350

TRUE

FALSE


None

MySQL with DRBDMySQL Simple Replication

MySQL Complex Replication

MySQL Cluster


32/42



Q16 Have you or your company ever outsourced programming duties?

0

50

100

150

200

250

300

117

270

TRUE

FALSE

Q17 Have you used the embedded version of MySQL (libmysqld)?

TRUE

FALSE0

50

100

150

200

250

300

350

400

40

341



33/42



Q18 Which connectors do you use? (multiple choice)

0

50

100

150

200

250

39

102

86

1611

35

43

197

133

40

None

MySQL C API

MySQL Connector/J

MySQL Connector/NET 5.1

MySQL Connector/NET 5.2

MySQL Connector/ODBC 3.x

MySQL Connector/ODBC 5.x

DBD::MySQL

PHP PDO_MYSQLND

Python DB-API

Q19 Which programming languages do you use?(multiple choic

C/C++

C#

JavaMono

PHP

Perl

Ruby

Python

VB .NET

Visual Basic

bash/csh/ksh/zsh

Other0

50

100

150

200

250

300

110

32

124

5

247

218

46

75

18 20

138

29

Surveycontinues on next pa


34/42



Q20 Do you identify yourself as part of the community of MySQL users?

0

20

40

60

80

100

120

140

160

180

142

162

75

13

Yes

Somewhat

No

Don't Care

Q21 Do you use the MySQL Forge?

Yes

Somewhat

No

Don't Care0

20

40

60

80

100

120

140

160

180

142

162

75

13



35/42




Q22 Have you reported MySQL bugs?

0

50

100

150

200

250

300

126

266

TRUE

FALSE

Q23 Have you contributed to MySQL documentation

TRUE

FALSE0

50

100

150

200

250

300

350

400

33

357


36/42




Q24 Have you contributed code to MySQL?

0

50

100

150

200

250

300

350

400

22

367

TRUE

FALSE

Q25 How often do you blog about MySQL?

Never

Multiple times a week.

Once a week.

Bimonthly

Once a month.

Every other month.

Too infrequent to remember.0

50

100

150

200

250

215

1318

14

2431

82


37/42




Q26 What is your favorite blog?BlogBlogBlogBlog CountCountCountCount

http://www.mysqlperformance.com 100http://www.planetmysql.com 77xaprb (Baron Schwartz) 44datacharmer (Giuseppe Maxia) 19krow (Brian Aker) 14Jay Pipes 10Pythian 9Jeremy Cole 8Sheeri Cabral 7Keith Murphy 7Q27 With the recent discussion on oursql-sources mailing list regrading the MySQL Contributor License

Agreement (CLA), should MySQL change the CLA to make it easier for the community to contribute code back

to MySQL?

0

20

40

60

80

100

120

140

160

180

165

Yes

No

Don't Care


38/42




Q28 Do you think the community edition of MySQL will fork if the current CLA remains unchanged?

0

20

40

60

80

100

120

140

160

180

110

117

154

Yes

No

Don't Care

Q29 Which storage engines do you use? (multiple choice)

MyISAM

InnoDB

MERGEMEMORY (HEAP)

BDB

EXAMPLE

FEDERATED

ARCHIVE

CSV

BLACKHOLE

FALCON0

50

100

150

200

250

300

350

400

344 344

37

100

102

3037

2026

6


39/42




Q30 The main reason for using Innodb?

0

50

100

150

200

250

192

78 78

33 Transaction support

Row-level locking

Foreign key support

I don't use InnoDB Q31 Do you use Federated?

Yes, in production

No, but I've tried it

No, I haven't tried it

I don't know what Federatedis

0

50

100

150

200

250

19

70

191

112


40/42




Q32 I don't use federated because:

0

50

100

150

200

250

212

8

35

24

I don't need it

It doesn't have the features Ineed

It's not stable enough

It's not efficient

Q33 What is most important to you about MySQL server?

Performance

Reliability

Ease of Use

Other0

20

40

60

80

100

120

140

160

139 140

70

34


41/42



Q34 Are you a current customer of Sun/MySQL?

0

50

100

150

200

250

300

350

89

301

TRUE

FALSE


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