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# Tag: Hacks

## Reading results of SHOW statements, on server side

MySQL common_schema Hacks INFORMATION_SCHEMA SQL November 25, 2011

SHOW statements are show stoppers on server side. While clients can get a SHOW statement as a result set just as any normal SELECT, things are not as such on server side.

On server side, that is, from within MySQL itself, one cannot:

>     SELECT `Database` FROM (SHOW DATABASES);

One cannot:

>     DECLARE show_cursor CURSOR FOR SHOW TABLES;

One cannot:

>     SHOW TABLES INTO OUTFILE '/tmp/my_file.txt';

So it is impossible to get the results with a query; impossible to get the results from a stored routine; impossible to get the results by file reading…

#### Bwahaha! A hack!

For some SHOW statements, there is a way around this. I’ve been banging my head against the wall for weeks now on this. Now I have a partial solution: I’m able to read SHOW output for several SHOW statements. Namely, those SHOW statements which allow a LIKE or a WHERE clause.

For example, most are familiar with the following syntax:

>     USE mysql;
>     SHOW TABLE STATUS LIKE 'user';

However not so many know that any SHOW statement which accepts LIKE, can also accept WHERE: Continue reading » “Reading results of SHOW statements, on server side”