我創建一個表像這樣: SELECT t1.c1, t2.c2, t3.c3, *several more columns*
INTO t4
FROM t1
INNER JOIN t2 ON t1.j2 = t2.j2
INNER JOIN t3 ON t1.j3 = t3.j3;
然後,我創建了一個聚集主鍵: ALTER TABLE t4 ADD CONSTRAINT pk_t4 PR
聲明: CREATE OR REPLACE FUNCTION test123(fstname text) RETURNS text AS $$ 和 CREATE OR REPLACE FUNCTION test123(fstname text) RETURNS text AS ' 當參數傳遞返回相同的數值。那麼這兩個陳述之間有什麼區別?
CREATE OR REPLACE FUNCTION array_replace(INT[]) RETURNS float[] AS $$
DECLARE
arrFloats ALIAS FOR $1;
J int=0;
x int[]=ARRAY[2,4];
-- xx float[]=ARRAY[2.22,4.33];
b float=2.2