sql查询所有表名和字段名称

sql server:

SELECT   
 d.name, ----(case when a.colorder=1 then d.name else '' end) as 表名,--如果表名相同就返回空  
     a.colorder as 字段序号,  
     a.name as 字段名,  
     (case when COLUMNPROPERTY( a.id,a.name,'IsIdentity')=1 then '√'else '' end) as 标识,  
     (case when (SELECT count(*) FROM sysobjects--查询主键  
                     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) as 主键,--查询主键END  
 b.name as 类型,  
 a.length as 占用字节数,  
 COLUMNPROPERTY(a.id,a.name,'PRECISION') as  长度,  
 isnull(COLUMNPROPERTY(a.id,a.name,'Scale'),0) as 小数位数,  
 (case when a.isnullable=1 then '√'else '' end) as 允许空,  
 isnull(e.text,'') as 默认值,  
 isnull(g.[value],'') AS 字段说明   
 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    where a.name='IsOwnerMerger'
 order by a.id,a.colorder

oracle:

获取表字段：

select * 
from user_tab_columns 
where Table_Name='用户表' 
order by column_name

获取表注释：

select * 
from user_tab_comments 
where Table_Name='用户表'

order by Table_Name

获取字段注释：

select * 
from user_col_comments 
where Table_Name='用户表'

order by column_name



/* 获取表：*/

select table_name from user_tables; //当前用户的表      

select table_name from all_tables; //所有用户的表  

select table_name from dba_tables; //包括系统表

select table_name from dba_tables where owner='zfxfzb'

/* 
user_tables：

table_name,tablespace_name,last_analyzed等

dba_tables：

ower,table_name,tablespace_name,last_analyzed等

all_tables：

ower,table_name,tablespace_name,last_analyzed等

all_objects：

ower,object_name,subobject_name,object_id,created,last_ddl_time,timestamp,status等 
*/

/*  获取表字段：*/

select * from user_tab_columns where Table_Name='用户表';

select * from all_tab_columns where Table_Name='用户表';

select * from dba_tab_columns where Table_Name='用户表';

/* user_tab_columns：

table_name,column_name,data_type,data_length,data_precision,data_scale,nullable,column_id等

all_tab_columns ：

ower,table_name,column_name,data_type,data_length,data_precision,data_scale,nullable,column_id等

dba_tab_columns：

ower,table_name,column_name,data_type,data_length,data_precision,data_scale,nullable,column_id等 
*/

/*  获取表注释：*/

select * from user_tab_comments

/* 
user_tab_comments：table_name,table_type,comments

相应的还有dba_tab_comments，all_tab_comments，这两个比user_tab_comments多了ower列。 
*/

/* 获取字段注释：*/

select * from user_col_comments

/*

user_col_comments：table_name,column_name,comments

相应的还有dba_col_comments，all_col_comments，这两个比user_col_comments多了ower列。 
*/

转载自：http://www.cnblogs.com/emanlee/archive/2011/12/02/2272629.html