Home Database Mysql Tutorial mysql中列信息查询(information

mysql中列信息查询(information

Jun 07, 2016 pm 03:39 PM
mysql information Inquire

当前数据库中当前用户可以访问的每一个列在该视图中占一行。 INFORMATION_SCHEMA.COLUMNS 视图以 sysobjects 、 spt_data type_info 、 systypes 、 syscolumns 、 syscomments 、 sysconfigures 以及 syscharsets 系统表为基

当前数据库中当前用户可以访问的每一个列在该视图中占一行。INFORMATION_SCHEMA.COLUMNS 视图以 sysobjectsspt_data type_infosystypessyscolumnssyscommentssysconfigures 以及 syscharsets 系统表为基础。

若要从这些视图中检索信息,请指定完全合格的 INFORMATION_SCHEMA view_name 名称。

列名 数据类型 描述
TABLE_CATALOG nvarchar(128) 表限定符。
TABLE_SCHEMA nvarchar(128) 表所有者。
TABLE_NAME nvarchar(128) 表名。
COLUMN_NAME nvarchar(128) 列名。
ORDINAL_POSITION smallint 列标识号。
COLUMN_DEFAULT nvarchar(4000) 列的默认值。
IS_NULLABLE varchar(3) 列的为空性。如果列允许 NULL,那么该列返回 YES。否则,返回 NO。
DATA_TYPE nvarchar(128) 系统提供的数据类型。
CHARACTER_MAXIMUM_LENGTH smallint 以字符为单位的最大长度,适于二进制数据、字符数据,或者文本和图像数据。否则,返回 NULL。有关更多信息,请参见数据类型。
CHARACTER_OCTET_LENGTH smallint 以字节为单位的最大长度,适于二进制数据、字符数据,或者文本和图像数据。否则,返回 NULL。
NUMERIC_PRECISION tinyint 近似数字数据、精确数字数据、整型数据或货币数据的精度。否则,返回 NULL。
NUMERIC_PRECISION_RADIX smallint 近似数字数据、精确数字数据、整型数据或货币数据的精度基数。否则,返回 NULL。
NUMERIC_SCALE tinyint 近似数字数据、精确数字数据、整数数据或货币数据的小数位数。否则,返回 NULL。
DATETIME_PRECISION smallint datetime 及 SQL-92interval 数据类型的子类型代码。对于其它数据类型,返回 NULL。
CHARACTER_SET_CATALOG varchar(6) 如果列是字符数据或 text 数据类型,那么返回 master,指明字符集所在的数据库。否则,返回 NULL。
CHARACTER_SET_SCHEMA varchar(3) 如果列是字符数据或 text 数据类型,那么返回 DBO,指明字符集的所有者名称。否则,返回 NULL。
CHARACTER_SET_NAME nvarchar(128) 如果该列是字符数据或 text 数据类型,那么为字符集返回唯一的名称。否则,返回 NULL。
COLLATION_CATALOG varchar(6) 如果列是字符数据或 text 数据类型,那么返回 master,指明在其中定义排序次序的数据库。否则此列为 NULL。
COLLATION_SCHEMA varchar(3) 返回 DBO,为字符数据或 text数据类型指明排序次序的所有者。否则,返回 NULL。
COLLATION_NAME nvarchar(128) 如果列是字符数据或 text 数据类型,那么为排序次序返回唯一的名称。否则,返回 NULL。
DOMAIN_CATALOG nvarchar(128) 如果列是一种用户定义数据类型,那么该列是某个数据库名称,在该数据库名中创建了这种用户定义数据类型。否则,返回 NULL。
DOMAIN_SCHEMA nvarchar(128) 如果列是一种用户定义数据类型,那么该列是这种用户定义数据类型的创建者。否则,返回 NULL。
DOMAIN_NAME nvarchar(128) 如果列是一种用户定义数据类型,那么该列是这种用户定义数据类型的名称。否则,返回 NULL。
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