--disable_query_log set @@session.explicit_defaults_for_timestamp=off; --enable_query_log # owner: link.zt # owner group: sql4 # description: from子查询测试集 --disable_warnings DROP TABLE IF EXISTS t1; --enable_warnings --disable_warnings DROP TABLE IF EXISTS t2; --enable_warnings #--real_sleep 1 CREATE TABLE t1 (pk int primary key,c1 INT, c2 CHAR(100),c3 FLOAT); #--real_sleep 1 SELECT * FROM t1 where pk = 1; INSERT INTO t1 VALUES (1, null,null,0.0); INSERT INTO t1 VALUES (2, 1,'',1.0); INSERT INTO t1 VALUES (3, 2,'abcde',2.0); INSERT INTO t1 VALUES (4, 100,'abcdefghij',3.0); CREATE TABLE t2 (pk int primary key,c1 INT, c2 VARCHAR(100)); #--real_sleep 1 INSERT INTO t2 VALUES (1, 1,'abcde'); INSERT INTO t2 VALUES (2, 2,'abcde'); SELECT sb1,sb2,sb3 FROM (SELECT c1 AS sb1, c2 AS sb2, c3*2 AS sb3 FROM t1) AS sb WHERE sb1 > 1; SELECT AVG(sum_column1) FROM (SELECT SUM(c1) AS sum_column1 FROM t1 GROUP BY c1) AS t1; DROP TABLE t1; DROP TABLE t2; #--real_sleep 1 CREATE TABLE t1 (pk int primary key, c1 INT, c2 VARCHAR(100),c3 FLOAT); #--real_sleep 1 INSERT INTO t1 VALUES (1, null,null,0.0); INSERT INTO t1 VALUES (2, 1,'',1.0); INSERT INTO t1 VALUES (3, 2,'abcde',2.0); INSERT INTO t1 VALUES (4, 100,'abcdefghij',3.0); CREATE TABLE t2 (pk int primary key, c1 INT, c2 VARCHAR(100)); #--real_sleep 1 INSERT INTO t2 VALUES (1, 1,'abcde'); INSERT INTO t2 VALUES (2, 2,'abcde'); SELECT sb1,sb2,sb3 FROM (SELECT c1 AS sb1, c2 AS sb2, c3*2 AS sb3 FROM t1) AS sb WHERE sb1 > 1; SELECT AVG(sum_column1) FROM (SELECT SUM(c1) AS sum_column1 FROM t1 GROUP BY c1) AS t1; DROP TABLE t1; DROP TABLE t2;