我研究了这些链接：
DatabaseError：用作表达式的子查询返回的不止一行（Django）
...但是他们似乎在他们的查询中使用了各种过滤，或者他们有子选择，当期望一行时返回多行。我的查询更简单，不应该期望只返回一行（据我所知）。我只是想使用 postgresql-9.1 从视图中全选：
# select * from MYVIEW;
ERROR: more than one row returned by a subquery used as an expression
而这有效：
# SELECT COUNT(*) FROM MYVIEW;
count
-------
5
(1 row)
这是我的观点的一般定义（请注意，以下内容仅供参考我从中选择的内容，而不是收到错误的内容。仅在运行上面发布的“全选”时收到错误） ：
CREATE VIEW MYVIEW(ID1, ID2, ID3, KEY1, KEY2, ID4, TXT1, ID5, LOC1) AS
SELECT
TABLE1.ID1,
(SELECT VALUE FROM TABLE2 WHERE TABLE3.TABLE3_ID = TABLE2.TABLE3_ID AND NAME = 'blah1' ) as ID2,
(SELECT VALUE FROM TABLE2 WHERE TABLE3.TABLE3_ID = TABLE2.TABLE3_ID AND NAME = 'blah2' ) as ID3,
(SELECT VALUE FROM TABLE2 WHERE TABLE3.TABLE3_ID = TABLE2.TABLE3_ID AND NAME = 'blah3') as KEY1,
(SELECT VALUE FROM TABLE2 WHERE TABLE3.TABLE3_ID = TABLE2.TABLE3_ID AND NAME = 'blah4') as KEY2,
TABLE4.ID6,
TABLE4.NAME,
ID5,
coalesce(
(SELECT VALUE FROM TABLE5 WHERE TABLE5.ID5 = TABLE6.ID5 AND NAME = 'BLAH5'),
(SELECT VALUE FROM TABLE7 WHERE TABLE7.ID6 = TABLE6.ID6 AND NAME = 'BLAH5' )
) as LOC1
FROM TABLE3, TABLE6, TABLE1, TABLE4, TABLE8
WHERE
TABLE3.TABLE8_ID = TABLE8.TABLE8_ID AND
TABLE3.ID1 = TABLE1.ID1 AND
TABLE8.TABLE8_ID = TABLE4.TABLE8_ID AND
TABLE4.ID6 = TABLE6.ID6 AND
TABLE6.TABLE3_ID = TABLE3.TABLE3_ID and
TABLE8.NAME = 'BLAH6' and
TABLE8.on = true and
TABLE4.ON = true and
TABLE6.ON = true and
TABLE1.ON = true AND
TABLE3.ON = TRUE;