sqlserver 常见使用sql

1使用某个库

 use hongqiao_oa;

2  查询当前数据库有哪些表
 
 SELECT Name FROM Master..SysDatabases ORDER BY Name
 SELECT 'select * from '+Name+';' FROM SysObjects Where XType='U' ORDER BY Name;
 

SELECT * FROM SysObjects ;

3 查询表结构信息

SELECT (case when a.colorder=1 then d.name else null end) 表名,  a.colorder 字段序号,a.name 字段名,(case when COLUMNPROPERTY( a.id,a.name,'IsIdentity')=1 then '√'else '' end) 标识,  (case when (SELECT count(*) FROM sysobjects   WHERE (name in (SELECT name FROM sysindexes   WHERE (id = a.id) AND (indid in   (SELECT indid FROM sysindexkeys   WHERE (id = a.id) AND (colid in   (SELECT colid FROM syscolumns WHERE (id = a.id) AND (name = a.name)))))))   AND (xtype = 'PK'))>0 then '√' else '' end) 主键,b.name 类型,a.length 占用字节数,  COLUMNPROPERTY(a.id,'PRECISION') as 长度,  isnull(COLUMNPROPERTY(a.id,'Scale'),0) as 小数位数,(case when a.isnullable=1 then '√'else '' end) 允许空,  isnull(e.text,'') 默认值,isnull(g.[value],' ') AS [说明] 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 sys.extended_properties g on a.id=g.major_id AND a.colid=g.minor_id left join sys.extended_properties f on d.id=f.class and f.minor_id=0 where b.name is not null and d.name='tbl_MD_Account' --如果只查询指定表,加上此条件 order by a.id,a.colorder