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Your subquery is selecting two columns, while you are using it to project one column (as part of the outer SELECT clause). You can only select one column from such a query in this context.
6 Οκτ 2021 · The error Operand should contain 1 column(s) is most likely caused by a subquery that’s returning more than one column. Here’s a typical SELECT query that causes this error: SELECT column_one, (SELECT column_two, column_three FROM table_two) FROM table_one;
Just make the 2nd test for b being greater than c in the ELSE of the first if statement. IF (a>b AND a>c,'a is greatest',IF (b>c,'b is greatest','c is greatest')) AS greatest. FROM test. Using CASE: Note I've used COALESCE (column, to avoid NULL values for a, b or c.
25 Ιαν 2013 · However, ideally you should consider normalizing the team table so you have one column with the player name and another column that assigns them a player number. Similar to this: create table team ( player varchar(50), playerNumber int ); Then when you are searching the team data you only have to join on one column instead of 8 different columns.
14 Οκτ 2015 · I'm running this query in MYSQL and I'm getting the error 1241: Operand should contain 1 column (s). I want to know the names and student id's of the students enrolled in Database Management Systems and Knowledge Discovery in Databases (both course titles in the CoursesOffer table)
ERROR 1241 (ER_OPERAND_COL) SQLSTATE = 21000 Message = "Operand should contain 1 column(s)" This error occurs in cases like this: SELECT (SELECT column1, column2 FROM t2) FROM t1; You may use a subquery that returns multiple columns, if the purpose is row comparison.
I have seen the success of using n != (select min (n) from a) and n != (select max (n) from a), but I did not know why my code went wrong. My guess is that it's because ' SELECT MAX(n), MIN(n) FROM a ' will generate two columns, rather than two rows. While I still don't know the exact reason.
