IF EXISTS (SELECT * FROM SYSINDEXES WHERE NAME='IX_factory_qrcode_old_dh')--检测是否已经存在IX_TEST_TNAME索引
DROP INDEX factory_qrcode_old.IX_factory_qrcode_old_dh--如果存在则删除
--创建索引
CREATE NONCLUSTERED INDEX IX_factory_qrcode_old_dh --创建一个非聚集索引
ON factory_qrcode_old(danhao) --为TEST表的TNAME字段创建索引