CodePudding user response:
Group by the back to add a having filteringCodePudding user response:
havingCodePudding user response:
Polymerization of filter, please refer to the aggregate function of filtration methodCodePudding user response:
Parameter description:Group field, is the mark to distinguish between individual data, can be one of the data of id, specific to the actual situation shall prevail;
A, b, c is the title of multiple fields;
Implementation of SQL is as follows:
A SELECT group field, sum (a + b + c)
FROM the table name
GROUP BY GROUP field
HAVING the sum (a + b + c)=0.