如果表中存在变量，如何检查SQL

Question

I'm creating function (PHP) which has to run every few hours and update some DB table. 1. If row isn't exist - INSERT new row 2. If row exist - UPDATE the current row

I want to write it the easiest and simplest way cause I'll do it for several tables.

Answer 1

You use the insert . . . on duplicate key update statement:

insert into dbtable(cols, . . . )
    select <values here >
    on duplicate key update col2 = values(col2), col3 = values(col3);

It is documented here.

EDIT:

Assuming you have some unique key on animals, your query would look something like:

insert into animals(animal_id, animal_name)
    select @animal_id, @animal_name
    on duplicate key update animal_name = values(animal_name);