Question

I want to copy data from two columns in a ‘table1’ to another table ‘table2’ which is empty and has two columns.

insert into users_role_map (email,id) select (email,roleId) from usert ;

when I try to do this I get the error

Operand should contain 1 column(s)

when I try to do the same thing with just one column I am able to copy the entire column data but not for the two columns simultaneously.Can any one help me out and guide me where I am going wrong.

Answer 1

Just remove the () from the SELECT statement. They are being parsed as though you were going to do an operation on a column like (id * 9), but MySQL then expects only one column inside the () as an operand. In any case, it’s a total misinterpretation by the query parser, and you should have no ().

INSERT INTO users_role_map (email, id)
   SELECT  email, roleId  FROM usert ;