10 stupid tips for MySQL

Você pode ler este post em português também. Hello! The April’s post brings 10 stupid tips for day-by-day work with MySQL. Let’s see them:

1. Use a .my.cnf file in your homedir with user/password data:

    \[client\]
    user=root
    password=my\_p@ss-w0rd

2. End your commands with \G instead of ";": This will bring a “form” view instead the normal tabular view. This is necessary a lot of times;

3. Materialized views: When the regular views (created with CREATE VIEW) doesn’t offer the expected performance, use triggers to feed tables that could work like the regular views. Being carefull, it helps a lot!

4. Take care of the parameter ENGINE of your databases and tables: Choose the best considering the R/W relation of the tables;

5. Adjust your MySQL prompt to your best fit at your .my.cnf in your homedir. The example below shows "mysql:db_name>". There are also the \u (to show the username) and \h (to show the hostname):

    prompt='mysql:\\d>'

6. At your mysql prompt, CTRL+A brings you to the begin of the line. CTRL+E brings you to the end;

7. To create a t2 table with the same structure of t1 table:

    CREATE TABLE t2 LIKE t1;

8. To create a user and give its access in one line:

    GRANT ALL ON db\_name.\* TO 'username'@'host' IDENTIFIED BY 'password'; FLUSH PRIVILEGES;

9. To generate a CSV file from the shell (better than OUTFILE ‘cause this below shows the column names):

    mysql -AD dbname -e "Your SELECT here;" | tr "\\t" ";" > resultset.csv

10. And the last, but not least (stupid). To show the queries in execution (the FULL parameter is optional):

SHOW \[FULL\] PROCESSLIST;

Memorize them and your day-by-day with MySQL will be easier. See you!