Mysql查询失败铺设了我

Everything was working fine before I upgraded my mysql version on server.

But now it's giving error and shows query failure. I have changed nothing in code.

SELECT id,frequency,speed FROM signal where active='Y'

It's showing error in from clause.Why this happening ?

Seems you upgraded in Mysql5.5 and SIGNAL is new reserved keyword in Mysql5.5. Escape your table name signal with backticks(`) in query.

Try below :

 SELECT id,frequency,speed FROM `signal` where active='Y'

SIGNAL is a MySQL reserved word, apparently. Enclose it in backquotes.

SELECT id,frequency,speed FROM `signal` where active='Y'

Whenever I get an error I don't expect in the FROM clause or elsewhere when the query appears to be syntactically correct, I consult the reserved words list for something I wasn't aware was reserved (and I admit I wasn't aware SIGNAL was reserved until I checked the list).

A bit of research hasn't pinned down when SIGNAL was added yet, but I suspect it was in MySQL 5.5.