The table name cannot be changed, that is to say, the data after from cannot be used to judge
Format if (expr, result1, result2 if expri is true, return result1, otherwise return result2
Think about the case field when zhen else end
The table name cannot be changed, that is to say, the data after from cannot be used to judge
Format if (expr, result1, result2 if expri is true, return result1, otherwise return result2
Think about the case field when zhen else end