desc 表名
你用的什么查询器?是pl/sql么?一般查询器,用ctrl+鼠标左键 点击表名的话,都会弹出表的结构的。
分两种方法:
1、在命令窗口通过如下语句:
desc 表名;
2、用语句:
select COLUMN_NAME,DATA_TYPE,DATA_LENGTH from user_tab_cols where table_name='TEST';
查询MySQL数据库所有表名的SQL命令:
show tables;
查询MySQL数据库有表结构的SQL命令:
show create table tblName;
例如:show create table students;
CREATE TABLE `students` (
`sid` char(10) NOT NULL,
`sname` varchar(50) NOT NULL,
`sex` char(1) NOT NULL,
`dob` date NOT NULL,
`phone` varchar(30) DEFAULT NULL,
PRIMARY KEY (`sid`),
KEY `index_tbl1_url` (`phone`(20))
) ENGINE=InnoDB DEFAULT CHARSET=gb2312
下边是SQLSERVER查询数据字典的语法,如果相查某一个表,只需要加where条件一个表名的连接即可。
SELECT TOP 100 PERCENT --a.id,
CASE WHEN a.colorder = 1 THEN d.name ELSE '' END AS 表名,
丹CASE WHEN a.colorder = 1 THEN isnull(f.value, '') ELSE '' END AS 表说明,
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 EXISTS
(SELECT 1
FROM dbo.sysindexes si INNER JOIN
dbo.sysindexkeys sik ON si.id = sik.id AND si.indid = sik.indid INNER JOIN
dbo.syscolumns sc ON sc.id = sik.id AND sc.colid = sik.colid INNER JOIN
dbo.sysobjects so ON so.name = si.name AND so.xtype = 'PK'
WHERE sc.id = a.id AND sc.colid = a.colid) THEN '√' ELSE '' END AS 主键,
b.name AS 类型, a.length AS 长度, COLUMNPROPERTY(a.id, a.name, 'PRECISION')
AS 精度, 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, d.crdate AS 创建时间,
CASE WHEN a.colorder = 1 THEN d.refdate ELSE NULL END AS 更改时间
FROM dbo.syscolumns a LEFT OUTER JOIN
dbo.systypes b ON a.xtype = b.xusertype INNER JOIN
dbo.sysobjects d ON a.id = d.id AND d.xtype = 'U' AND
d.status >= 0 LEFT OUTER JOIN
dbo.syscomments e O......更多唯美的句子:www.gulongbbs.cn
1、登录plsql
2、点击左上角小白纸片,新建-命令窗口
3、输入:desc 表名;
这就是表结构了
1.show tables
2.desc 表名
informix查询表结构方法有多种,可以通过系统信息表查询,也可以通过系统功能查询
查询系统表存储信息步骤:
登录数据库
dbaccess xxxdb ;
执行查询语句
SELECT c.colname[1,20], c.coltype, c.collength
FROM syscolumns c, systables t
WHERE c.tabid = t.tabid
AND t.tabname = 'xxxTable';
通过系统提供的命令功能查询:
dbaccess - info 查询表信息
dbschema命令导出表结构
rs不知是什么东西..
用sql语句行不行?
select COLUMN_NAME,DATA_TYPE from USER_TAB_COLS where TABLE_NAME='TEST';
现提供两条命令查询表结构:1.sp_help table_name;如:sp_help Student;2.sp_columnstable_name;如:sp_columns Student;
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