SQL 某一列是不是关键字的判断,
由于写一个代码自动生成工具,需要找一些读系统数据字典的信息,
以前有个写一个很不错的,
SELECT 表名=case when a.colorder=1 then d.name else '' end, 字段序号=a.colorder, 字段名=a.name, 标识=case when COLUMNPROPERTY( a.id,a.name,'IsIdentity')=1 then '√'else '' end, 主键=case when exists(SELECT 1 FROM sysobjects where xtype='PK' and name in ( SELECT name FROM sysindexes WHERE indid in( SELECT indid FROM sysindexkeys WHERE id = a.id AND colid=a.colid ))) then '√' else '' end, 类型=b.name, 占用字节数=a.length, 长度=COLUMNPROPERTY(a.id,a.name,'PRECISION'), 小数位数=isnull(COLUMNPROPERTY(a.id,a.name,'Scale'),0), 允许空=case when a.isnullable=1 then '√'else '' end, 默认值=isnull(e.text,''), 字段说明=isnull(g.[value],'')FROM syscolumns a left join systypes b on a.xtype=b.xusertype inner join sysobjects d on a.id=d.id and d.xtype='U' and d.name<>'dtproperties' left join syscomments e on a.cdefault=e.id left join sysproperties g on a.id=g.id and a.colid=g.smallid order by a.id,a.colorder
我也按字的方法来读,
但是今天发现,主键,信息不是很正确,
一看代码,读主键,那要跟索引结合起来的,
于是上网找相关资料,找了半天,也没有找到,
于是就自己看SQL server的帮助,
最后发现,
syscolumns的status为128就是主键,
SELECT ColumnName = a.name, Type = b.name,Length3 =COLUMNPROPERTY(a.id,a.name,'PRECISION'),
IsKey = CASE a.status WHEN 128
THEN '1' ELSE '0' END,
Length1 = a.length, Length2 = isnull(COLUMNPROPERTY(a.id, a.name, 'Scale'), 0),IsIdentity = CASE WHEN COLUMNPROPERTY(a.id, a.name, 'IsIdentity') = 1 THEN '1' ELSE '0' END
FROM syscolumns a LEFT JOIN
systypes b ON a.xtype = b.xusertype INNER JOIN sysobjects d ON a.id = d .id AND d .xtype = 'U' AND d .name <> 'dtproperties' LEFT
JOIN syscomments e ON a.cdefault = e.id LEFT JOIN sysproperties g ON a.id = g.id AND a.colid = g.smallid
WHERE d .name = 'Users' ORDER BY a.id, a.colorder
以前有个写一个很不错的,
SELECT 表名=case when a.colorder=1 then d.name else '' end, 字段序号=a.colorder, 字段名=a.name, 标识=case when COLUMNPROPERTY( a.id,a.name,'IsIdentity')=1 then '√'else '' end, 主键=case when exists(SELECT 1 FROM sysobjects where xtype='PK' and name in ( SELECT name FROM sysindexes WHERE indid in( SELECT indid FROM sysindexkeys WHERE id = a.id AND colid=a.colid ))) then '√' else '' end, 类型=b.name, 占用字节数=a.length, 长度=COLUMNPROPERTY(a.id,a.name,'PRECISION'), 小数位数=isnull(COLUMNPROPERTY(a.id,a.name,'Scale'),0), 允许空=case when a.isnullable=1 then '√'else '' end, 默认值=isnull(e.text,''), 字段说明=isnull(g.[value],'')FROM syscolumns a left join systypes b on a.xtype=b.xusertype inner join sysobjects d on a.id=d.id and d.xtype='U' and d.name<>'dtproperties' left join syscomments e on a.cdefault=e.id left join sysproperties g on a.id=g.id and a.colid=g.smallid order by a.id,a.colorder
我也按字的方法来读,
但是今天发现,主键,信息不是很正确,
一看代码,读主键,那要跟索引结合起来的,
于是上网找相关资料,找了半天,也没有找到,
于是就自己看SQL server的帮助,
最后发现,
syscolumns的status为128就是主键,
SELECT ColumnName = a.name, Type = b.name,Length3 =COLUMNPROPERTY(a.id,a.name,'PRECISION'), IsKey = CASE a.status WHEN 128THEN '1' ELSE '0' END, Length1 = a.length, Length2 = isnull(COLUMNPROPERTY(a.id, a.name, 'Scale'), 0),IsIdentity = CASE WHEN COLUMNPROPERTY(a.id, a.name, 'IsIdentity') = 1 THEN '1' ELSE '0' END FROM syscolumns a LEFT JOIN systypes b ON a.xtype = b.xusertype INNER JOIN sysobjects d ON a.id = d .id AND d .xtype = 'U' AND d .name <> 'dtproperties' LEFT JOIN syscomments e ON a.cdefault = e.id LEFT JOIN sysproperties g ON a.id = g.id AND a.colid = g.smallid WHERE d .name = 'Users' ORDER BY a.id, a.colorder
