SQL : How can handle this ERROR 1242 (21000): Subquery returns more than 1 row

SQL : How can handle this ERROR 1242 (21000): Subquery returns more than 1 row
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SQL : How can handle this ERROR 1242 (21000): Subquery returns more than 1 row
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more returns (21000): can than 1 : SQL row 1242 handle this ERROR How Subquery