test=# create type inventory_item as (name text,sid int); CREATE TYPE test=# create table on_hand(item inventory_item); CREATE TABLE test=# insert into on_hand values(row('fkdsa',45)); INSERT 0 1 查找复合类型的列:select (item).name from on_hand;(如果item已经是表明的情况下,使用括...
CREATEOPERATORCLASSname[ DEFAULT ]FORTYPEdata_typeUSINGindex_method[ FAMILY family_name ]AS{OPERATORstrategy_numberoperator_name[ ( op_type, op_type ) ][ FOR SEARCH | FOR ORDER BY sort_family_name ]|FUNCTIONsupport_number[ ( op_type [ , op_type ]) ]function_name( argument_type [, ......
PostgreSQL has a rich set of native data types available to users. Users can add new types to PostgreSQL using the CREATE TYPE command. PostgreSQL有一组丰富的本地数据类型可供用户使用。用户可以使用CREATE TYPE命令向PostgreSQL添加新类型。Each data type has an external representation determined by its...
使用createuser 命令来创建一个数据库用户。postgres 用户是 Postgres 安装的超级用户。 创建一个数据库 复制 $ sudo-upostgres createuser--interactive--passwordbogus Shall the new role be a superuser? (y/n) n Shall the new role be allowed to create databases? (y/n) y Shall the new role be ...
使用createuser命令来创建一个数据库用户。postgres用户是 Postgres 安装的超级用户。 $ sudo -u postgres createuser --interactive --password bogus Shall the new role be a superuser? (y/n) n Shall the new role be allowed to create databases? (y/n) y ...
PostgreSQL 创建表格 PostgreSQL 使用 CREATE TABLE 语句来创建数据库表格。 语法 CREATE TABLE 语法格式如下: CREATE TABLE table_name( column1 datatype, column2 datatype, column3 datatype, ... columnN datatype, PRIMARY KEY( ..
A wide set of Data Types are available in PostgreSQL. Besides, users can create their own custom data type using "CREATE TYPE" command. In the rest of the document, we have discussed each of the PostgreSQL Data Types based on PostgreSQL 9.1 Version. ...
typedef struct nameData { char data[NAMEDATALEN]; } NameData; typedef NameData *Name; ,在物理文件的存储如下: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 postgres=# create table nametable(n1 name); CREATE TABLE postgres=# insert into nametable values ('liu'); INSERT 0 1 postgres...
CREATE or replace PROCEDURE tp12( a in integer, ---> function->fn_argvarnos b out integer, ---> function->out_param_varno c out integer, ---> function->out_param_varno d inout integer default 300, ---> function->fn_argvarnos --->function->out_param_varno e in integer default ...
CREATE CAST (source_type AS target_type) WITH INOUT [ AS ASSIGNMENT | ASIMPLICIT] 解释: 1、WITH FUNCTION,表示转换需要用到什么函数。 2、WITHOUT FUNCTION,表示被转换的两个类型,在数据库的存储中一致,即物理存储一致。例如text和varchar的物理存储一致。不需要转换函数。