请教select多表导入
我有三个表

table1          table2              table3

col1          col3  col4             col5    col6

a             a        5             a       6

b            c        7               b       2

c            d        9              d       3

d

想用select生成一表如下：

col1    col4    col6

a         5          6

b          0         2

c         7          0

d          9         3

sele table1.col1,iif(isnull(table2.col4),0,table2.col4) col4,iif(isnull(table3.col6),0,table3.col6) col6  from table1 left outer join table2 on table1.col1=table2.col3 left outer join table3 on table1.col1=table3.col5

[ 本帖最后由 tlliqi 于 2012-5-31 15:00 编辑 ]

CREATE CURSOR TABLE1 (COL1 C(1))
FOR I=1 TO 4
    INSERT INTO TABLE1 VALUES (CHR(96+I))
ENDFOR
CREATE CURSOR TABLE2 (COL3 C(1),COL4 N(1))
INSERT INTO TABLE2 VALUES ('a',5)
INSERT INTO TABLE2 VALUES ('c',7)
INSERT INTO TABLE2 VALUES ('d',9)
CREATE CURSOR TABLE3 (COL5 C(1),COL6 N(1))
INSERT INTO TABLE3 VALUES ('a',6)
INSERT INTO TABLE3 VALUES ('b',2)
INSERT INTO TABLE3 VALUES ('d',3)
SELECT TABLE1.COL1,IIF(ISNULL(TABLE2.COL4),0,TABLE2.COL4) AS COL4,IIF(ISNULL(TABLE3.COL6),0,TABLE3.COL6) AS COL6 FROM TABLE1 FULL JOIN TABLE2 ON TABLE2.COL3=TABLE1.COL1 FULL JOIN TABLE3 ON TABLE3.COL5=TABLE1.COL1 ORDER BY TABLE1.COL1 INTO CURSOR TABLE0
BROWSE

[ 本帖最后由 sdta 于 2012-5-31 13:10 编辑 ]

  SELECT DISTINCT table1.col1 table2.col4 table3.col6  from table1 table2 table2 where; table1.col1=table2.col1 and table2.col1=table3.col1  

谢谢,很有用,我正在找这个资料.