Open Software Solutions

To increment or decrement and existing number in a table (you do not need to read the value first)  please read on : Increment the value 'timer' by one for the row in table 'movies' where 'movie_id' is '24', use: UPDATE movies SET timer=timer+1 WHERE movie_id=24 Note  to decrement use timer=timer-1 Enjoy Read more..

This is how to remove a table from a MySQL database, and remove all of its data, use the following SQL command: 1.  log in mysql 2.  issue command : use yourdatabase;  3. issue command : drop table if exists yourtable; The last command will delete the database if it exists , it is usefull because if it does not exist it will not output any error Read more..

If you use  innodb tables and foreign key constraints, importing a mysqldump may generate foreign key errors. To resolve this issue please read on : At the beginning of the dump file add this : SET FOREIGN_KEY_CHECKS=0; At the end of the dump file add this : SET FOREIGN_KEY_CHECKS=1; This will disable foreign key checks for the mysqldump import session only. This will allow the data to be imported without the error being generated. Read more..

"error: 1016: Can't open file:" If it's from an orphaned file, not in the database but on disk, then, the disk file may need to be deleted. myisamchk can help with damaged files. It's best to stop the database. # su - # mysqladmin shutdown ... Read more..

Find out who is doing what, and kill the process if needed. This example kills Id 657. mysql> show processlist; show processlist; +-----+------+-----------+---------+---------+-------+-------+------------------+ | Id | User | Host | db | Command | Time | State | Info | ... Read more..

Clean up binary log files. For a default install they may be in /usr/local/var/ or /var/lib/mysql/ with names ending in -bin.000001,-bin.000002,.. The following command may help find out where the logs are located. mysql> show variables like '%home%'; ... Read more..

MySQL Replace(), here's the syntax. update [table_name] set [field_name] = replace([field_name],'[string_to_find]','[string_to_replace]'); Read more..

Print defaults for the current client connection $ my_print_defaults client mysql --port=3306 --socket=/tmp/mysql.sock --no-auto-rehash Note, for client connections, you can put setting in the user's .my.cnf file. ... Read more..

MERGE: Several tables can be merged into one. CREATE TABLE log_01 ( pkey int(11) NOT NULL auto_increment, a int, b varchar(12), timeEnter timestamp(14), ... Read more..

Creating tables in databases is the  first step to store your data To create a table you must describe the columns and their atributes. We will create a table to hold contact information with four columns: contact_id, name, email, and birthdate. contact_id column =  integer number that is 20 decimal places long ( it is created with an INT(20) datatype). name column holds the full name of a contact, which we  will will set be no longer than 50 characters long, so the ... Read more..

Transactions: Not all table types support transactions. BDB and INNODB type do support transactions. Assuming the server has NOT been started with --skip-bdb or --skip-innodb the following should work: mysql> create table tran_test (a int, b int) type = InnoDB; mysql> begin; mysql> insert into tran_test (a,b) values (1,2); ... Read more..

You can use mysql to import directly a csv file . You do not need to make a script to do this anymore From an Excel file , you need to export it as CSV ,  Remove the CSV Headers and the Excel data  from the file ,  and after that it can be inserted in MySql Here is an example : load data local infile 'your.csv' into table tblUniq fields terminated by ',' enclosed by '"' lines terminated by '\n' (yourName, yourCity, yourComments) Read more..

Can the order of the columns in a create statement make a difference? YES create table t ( a int, b int, timeUpdate timestamp, timeEnter timestamp ); The first timestamp will always be the "automatically ... Read more..

Quick Status: mysql> \s -------------- /usr/local/bin/mysql Ver 14.3 Distrib 4.1.1-alpha, for pc-linux (i686) Connection id: 642 Current database: Current user: prog@localhost SSL: ... Read more..

Remove duplicate entries. Assume the following table and data. CREATE TABLE IF NOT EXISTS dupTest ( pkey int(11) NOT NULL auto_increment, a int, ... Read more..

First step is to select a database , after that you can view the tables  1 . view all of the tables in the selected database : SHOW TABLES; 2.  view all of the tables in a different database (not selected): SHOW TABLES IN different_db; 3.  view a specific table in the selected  database : SHOW TABLES IN newDB LIKE '%time'; The above command will find all tables that end in "time"  from the database newDB Read more..

This is how to list the databases that exist in a MySQL server, use the 'show databases' SQL command: show databases; +------------------+ | Database                | +------------------+ | database1              | | mysql                     | | test                         | +------------------+ It will display all the databases your user has access to Read more..

Show status information on a table. Note, if the database was started with --safe-show-database or --skip-show-database some of these commands may not work. Note the "\G" option may provide a nicer format. Show the create statement: mysql> show create table dupTest\G ... Read more..

You do not need to enter mysql for this , here is the exact sintax you must use : mysqldump -u [username] -p [database_name] > /path/to/file.sql  example mysqldump -u mario  -p marioDB > /tmp/marioDB.sql Read more..

Recovering / Changing Your MySQL Root Password Sometimes you may have to recover the MySQL root password because it was either forgotten or misplaced. The steps you need are: 1) Stop MySQL [root@bigboy tmp]# service mysqld stop Stopping MySQL:  [  OK  ] [root@bigboy tmp]# 2) Start MySQL in Safe mode with the mysqld_safe command and tell it not to read the grant tables with all the MySQL database passwords. [root@bigboy tmp]# mysqld_safe --skip-grant-tables --skip-networking & [1] 13007 [root@bigboy tmp]# Starting mysqld daemon with databases from /var/lib/mysql [root@bigboy tmp]# Note: In Fedora ... Read more..