sql语句中select查询时什么时候加'*'号 sql 查询语句自动增加序号
sql\u7684\u67e5\u8be2\u8bed\u53e5\u4e2dselect*\u600e\u4e48\u7528\u5982\u679c\u60f3\u8981\u83b7\u5f97\u6240\u6709\u7684\u5b57\u6bb5\u6216\u8005\u4e0d\u77e5\u9053\u6709\u54ea\u4e9b\u5b57\u6bb5\u7684\u60c5\u51b5\u4e0b\u7528*\u4ee3\u8868\u6240\u6709\u5b57\u6bb5
SELECT + \u8868\u5b57\u6bb5\u540d + FROM +\u6570\u636e\u8868\u540d+ WHERE + \u7b5b\u9009\u6761\u4ef6
\u6bd4\u5982:
select * from Table1\uff0c\u6253\u5370\u6240\u6709\u7684Table1\u8868\u4e2d\u4fe1\u606f
select * from Table1 where name="aa"\uff0c\u6253\u5370Table1\u4e2dname\u4e3aaa\u7684\u6240\u6709\u4fe1\u606f
\u73b0\u6709\u4e24\u79cd\u65b9\u6cd5\u89e3\u51b3\uff0c\u4f9b\u53c2\u8003\uff1a1\u3001SELECT IDENTITY(INT,1,1) AS \u5e8f\u53f7, avge FROM Table12\u3001SELECT IDENTITY(INT,1,1) AS \u5e8f\u53f7, avge INTO #temp1 FROM Table1SELECT * FROM #temp1DROP TABLE #temp1
\u7ed9\u67e5\u8be2\u51fa\u7684SQL\u8bb0\u5f55\u6dfb\u52a0\u5e8f\u53f7\u5217\uff0c\u89e3\u51b3\u65b9\u6cd5\u6709\u4ee5\u4e0b\u4e24\u79cd \u7b2c\u4e00\uff1a
select ROW_NUMBER() OVER (ORDER BY a.\u5b57\u6bb5 ASC) AS XUHAO,a.* from table a1
(table \u4e3a\u8868\u540d\uff0c\u5b57\u6bb5\u4e3a\u8868a\u4e2d\u7684\u5b57\u6bb5\u540d) \u7b2c\u4e8c\uff1a
select RANK() OVER (ORDER BY a.\u5b57\u6bb5 ASC) AS XUHAO,a.* from table a1
(table \u4e3a\u8868\u540d\uff0c\u5b57\u6bb5\u4e3a\u8868a\u4e2d\u7684\u5b57\u6bb5\u540d)
select * from A
这里星号表示查询出表里面的全部字段，如果你不需要查询全部字段，就可以不使用星号，而是制定列出的字段。
比如：
select a1,a2,a3 from A
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