--测试表及数据
CREATE TABLE tb(Col varchar(10))
INSERT tb SELECT '1900-1-1'
UNION ALL SELECT '19aa-1-1'
GO
SELECT * FROM tb
WHERE ISDATE(Col)=1
AND Col<GETDATE()
GO
--建立索引
CREATE INDEX IDX_tb_Col ON tb(Col)
GO
SELECT * FROM tb
WHERE ISDATE(Col)=1
AND Col<GETDATE()
GO
--删除测试
DROP TABLE tb
