sqlite版本3.4.0
聚合函数有什么问题?此外,我怀疑ORDER BY也不会奏效.如何重写?
聚合函数有什么问题?此外,我怀疑ORDER BY也不会奏效.如何重写?
sqlite> SELECT p1.domain_id,p2.domain_id,COUNT(p1.domain_id) AS d1,COUNT(p2.domain_id) AS d2 ...> FROM PDB as p1,Interacting_PDBs as i1,PDB as p2,Interacting_PDBs as i2 ...> WHERE p1.id = i1.PDB_first_id ...> AND p2.id = i2.PDB_second_id ...> AND i1.id = i2.id ...> AND d1>100 ...> AND d2>100 ...> ORDER BY d1,d2; sql error: misuse of aggregate: sqlite>
解决方法
当使用聚合函数(sum / count / …)时,还必须使用GROUP BY子句.
接下来,当您要过滤汇总的结果时,您不能在WHERE子句中执行此操作,但必须在HAVING子句中执行该操作.
SELECT p1.domain_id,COUNT(p2.domain_id) AS d2 FROM PDB as p1,Interacting_PDBs as i2 WHERE p1.id = i1.PDB_first_id AND p2.id = i2.PDB_second_id AND i1.id = i2.id GROUP BY p1.domain_Id,p2.domain_Id HAVING d1 > 100 AND d2 > 100 ORDER BY d1,d2;