#1222 - The used SELECT statements have a different number of columns

Question

Why am i getting a #1222 - The used SELECT statements have a different number of columns ? i am trying to load wall posts from this users friends and his self.

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Answer 1

You are using MySQL Union.

UNION is used to combine the result from multiple SELECT statements into a single result set.

The column names from the first SELECT statement are used as the column names for the results returned. Selected columns listed in corresponding positions of each SELECT statement should have the same data type. (For example, the first column selected by the first statement should have the same type as the first column selected by the other statements.)

Reference: MySQL Union

Your first select statement has 4 columns and second statement has 6 as you said wall_post has 6 column. You should have same number of column and also in same order in both statement. otherwise it shows error or wrong data.