数据库:的Sybase优势11
在我的追求,以标准化的数据,我想删除的结果我从这个SELECT
说法得到:
SELECT tableA.entitynum
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum)
WHERE (LENGTH(q.memotext) NOT IN (8,9,10)
OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date')
;
这是DELETE
声明我想出了:
DELETE FROM tableA
WHERE (SELECT q.entitynum
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum)
WHERE (LENGTH(q.memotext) NOT IN (8,9,10)
OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date'))
;
当我尝试运行此声明我不断收到此错误:
ERROR IN SCRIPT: poQuery: Error 7200: AQE Error: State = S0000; NativeError = 2124;
[iAnywhere Solutions][Advantage SQL Engine]Invalid operand for operator: = Boolean value
cannot be operated with non-Boolean value.
我也试过这样一句话:
DELETE FROM tableA
INNER JOIN tableB u on (u.qlabel = tableA.entityrole AND u.fieldnum = tableA.fieldnum)
WHERE (LENGTH(q.memotext) NOT IN (8,9,10)
OR tableA.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date')
;
这会导致:
ERROR IN SCRIPT: poQuery: Error 7200: AQE Error: State = 42000; NativeError = 2117;
[iAnywhere Solutions][Advantage SQL Engine] Unexpected token: INNER -- Expecting semicolon.
-- Location of error in the SQL statement is: 23 (line: 2 column: 1)
可能有人帮助我正确地构建DELETE查询,将导致正确的数据被删除?
你需要确定以删除正确的记录TableA中的主键。主键可以是单个列或几列的组合唯一地标识在表中的行。如果没有主键,则ROWID伪列,可以使用作为主键。
DELETE FROM tableA
WHERE ROWID IN
( SELECT q.ROWID
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum)
WHERE (LENGTH(q.memotext) NOT IN (8,9,10) OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date'));
你的第二个DELETE
查询几乎是正确的。只是一定要放DELETE
和FROM
之间的表名(或别名)来指定要从中删除该表。这比使用嵌套SELECT
语句像其他答案简单。
DELETE tableA
FROM tableA
INNER JOIN tableB u on (u.qlabel = tableA.entityrole AND u.fieldnum = tableA.fieldnum)
WHERE (LENGTH(tableA.memotext) NOT IN (8,9,10)
OR tableA.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date')
DELETE q
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum)
WHERE (LENGTH(q.memotext) NOT IN (8,9,10)
OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date')
你不应该有:
DELETE FROM tableA WHERE entitynum IN (...your select...)
现在你只要有一个不带比较WHERE:
DELETE FROM tableA WHERE (...your select...)
所以,你最终的查询应该是这样的;
DELETE FROM tableA WHERE entitynum IN (
SELECT tableA.entitynum FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum)
WHERE (LENGTH(q.memotext) NOT IN (8,9,10) OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date')
)
在这种情况下:
DELETE FROM tableA
WHERE (SELECT q.entitynum
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum)
WHERE (LENGTH(q.memotext) NOT IN (8,9,10)
OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date'));
你不思念你要比较的列?例:
DELETE FROM tableA
WHERE entitynum in (SELECT q.entitynum
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum)
WHERE (LENGTH(q.memotext) NOT IN (8,9,10)
OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date'));
我想这是因为在你的SELECT语句,你是从你想从该列删除同一表中选择该列。
不喜欢的东西,一旦:
CREATE TABLE exclusions(excl VARCHAR(250));
INSERT INTO exclusions(excl)
VALUES
('%timeline%'),
('%Placeholders%'),
('%Stages%'),
('%master_stage_1205x465%'),
('%Accessories%'),
('%chosen-sprite.png'),
('%WebResource.axd');
GO
CREATE VIEW ToBeDeleted AS
SELECT * FROM chunks
WHERE chunks.file_id IN
(
SELECT DISTINCT
lf.file_id
FROM LargeFiles lf
WHERE lf.file_id NOT IN
(
SELECT DISTINCT
lf.file_id
FROM LargeFiles lf
LEFT JOIN exclusions e ON(lf.URL LIKE e.excl)
WHERE e.excl IS NULL
)
);
GO
CHECKPOINT
GO
SET NOCOUNT ON;
DECLARE @r INT;
SET @r = 1;
WHILE @r>0
BEGIN
DELETE TOP (10000) FROM ToBeDeleted;
SET @r = @@ROWCOUNT
END
GO