Skip to content
Advertisement

Tag: mysql

How to automatically convert a MySQL column to lowercase

Is there a property that I can add to a column so that it converts its value to lowercase? Instead of doing it for every single value through PHP? Answer You could probably do it through a trigger that fires on insert or update. Myself, I’d rather just create a view that has a lower-case version of the column in

MySQL OPTIMIZE all tables?

MySQL has an OPTIMIZE TABLE command which can be used to reclaim unused space in a MySQL install. Is there a way (built-in command or common stored procedure) to run this optimization for every table in the database and/or server install, or is this something you’d have to script up yourself? Answer You can use mysqlcheck to do this at

INSERT with SELECT

I have a query that inserts using a SELECT statement: Is it possible to only select “name, location” for the insert, and set gid to something else in the query? Answer Yes, absolutely, but check your syntax. You can put a constant of the same type as gid in its place, not just 1, of course. And, I just made

how to sort order of LEFT JOIN in SQL query?

OK I tried googling for an answer like crazy, but I couldn’t resolve this, so I hope someone will be able to help. Let’s say I have a table of users, very simple table: and I have another table of their cars and their prices. Now what I need to do is something like this (feel free to rewrite): Which

MySQL query finding values in a comma separated string

I have a field COLORS (varchar(50)) in a my table SHIRTS that contains a comma delimited string such as 1,2,5,12,15,. Each number representing the available colors. When running the query select * from shirts where colors like ‘%1%’ to get all the red shirts (color=1), I also get the shirts whose color is grey (=12) and orange (=15). How should

Two Inner Joins MYSQL

How would I preform two inner joins in one query? Ie: three tables Invoice Address Client Invoice has a column which references an id in clients. It also has a column which references an address. I need to get both the clients name from the matched table and the address from the matched table. How would I INNER JOIN both

Conditional NOT NULL case SQL

I am trying to calculate a field and I want it to behave differently depending on if one of the columns happens to be null. I am using MySQL Is this the right syntax? Answer You need to have when reply.replies IS NOT NULL NULL is a special case in SQL and cannot be compared with = or <> operators.

Advertisement