在DB2中显示表的定义

Question

大家好,我正在学习DB2,想知道在创建表之后如何查看表的特性.

类似于MySQL中的EXPLAIN TABLE命令.

谢谢.

Answer 1

除了DESCRIBE TABLE之外,您还可以使用以下内容

DESCRIBE INDEXES FOR TABLE *tablename* SHOW DETAIL 

获取有关表索引的信息.

有关DB2 for Linux,UNIX和Windows的表的最全面的详细信息可以从db2look实用程序获得,该实用程序可以从远程客户端运行,也可以作为本地用户直接在DB2服务器上运行.该工具生成DDL和模拟表及其统计数据所需的其他信息.DB2 9.5中的db2look文档就在这里.

以下DESCRIBE TABLE命令将连接到SALESDB数据库并获取重新创建ORDERS表所需的DDL命令

db2look -d SALESDB -e -t ORDERS

Answer 2

我知道这是一个老问题,但这将完成这项工作.

SELECT colname, typename, length, scale, default, nulls
  FROM syscat.columns
 WHERE tabname = '<table name>'
   AND tabschema = '<schema name>'
 ORDER BY colno

Answer 3

db2look -d <db_name> -e -z <schema_name> -t <table_name> -i <user_name> -w <password>> <file_name> .sql

欲了解更多信息,请参阅以下内容:

    db2look [-h]

    -d: Database Name: This must be specified

    -e: Extract DDL file needed to duplicate database
   -xs: Export XSR objects and generate a script containing DDL statements
 -xdir: Path name: the directory in which XSR objects will be placed
    -u: Creator ID: If -u and -a are both not specified then $USER will be used
    -z: Schema name: If -z and -a are both specified then -z will be ignored
    -t: Generate statistics for the specified tables
   -tw: Generate DDLs for tables whose names match the pattern criteria (wildcard characters) of the table name
   -ap: Generate AUDIT USING Statements
  -wlm: Generate WLM specific DDL Statements
  -mod: Generate DDL statements for Module
  -cor: Generate DDL with CREATE OR REPLACE clause
 -wrap: Generates obfuscated versions of DDL statements
    -h: More detailed help message
    -o: Redirects the output to the given file name
    -a: Generate statistics for all creators
    -m: Run the db2look utility in mimic mode
        -c: Do not generate COMMIT statements for mimic
        -r: Do not generate RUNSTATS statements for mimic
    -l: Generate Database Layout: Database partition groups, Bufferpools and Tablespaces
    -x: Generate Authorization statements DDL excluding the original definer of the object
   -xd: Generate Authorization statements DDL including the original definer of the object
    -f: Extract configuration parameters and environment variables
   -td: Specifies x to be statement delimiter (default is semicolon(;))
    -i: User ID to log on to the server where the database resides
    -w: Password to log on to the server where the database resides

Answer 4

描述表的语法

db2 describe table <tablename>

或所有表格详细信息

select * from syscat.tables

或所有表格详细信息

 select * from sysibm.tables

Answer 5

所有这些元数据都保存在“模式”的 DB2 目录表中SYSIBM。对于 DB2/z 大型机产品和 DB2/LUW 分布式产品来说，它有所不同，但它们在每个版本中都越来越接近。

IBM 方便地将所有手册放在publib网站上，供全世界访问。我的专业领域 DB2/z在这里有您想要的页面。

您需要参考许多表格：

SYSTABLES        for table information.
SYSINDEXES    \
SYSINDEXPART   + for index information.
SYSKEYS       /
SYSCOLUMNS       for column information.

所有信息中心的列表都在这里，如果您感兴趣的话，它应该会引导您找到 DB2/LUW 版本。