SELECT AVG(t2.a - t1.a) AS "avg",AVG(t2.a + t1.a) AS "avg1",
AVG(t2.a - t1.b) AS "avg2", SUM(t2.a * t1.a) AS "avg3", 
SUM(t2.a / t1.a) AS "avg4",AVG(t2.b * t1.b) AS "avg5", 
MAX(t2.b - t2.a) AS "max", MIN(t2.b - t2.a) AS "min", 
SUM(t2.a + t2.a) AS "sum", MAX(t2.a * t1.a) AS "max2", 
MIN(t2.b / t2.a) AS "min2", MAX(t2.a + t1.a) AS "max3", 
MIN(t2.b / t1.b) AS "min4", SUM(t2.a * t1.b) AS "sum4", 
SUM(t1.b - t1.b) AS "sum5"  
FROM t1, t2;