CREATE [ UNIQUE ] INDEX [ CONCURRENTLY ] [ [ IF NOT EXISTS ] name ] ON [ ONLY ] table_name [ USING method ] ( { column_name | ( expression ) } [ COLLATE collation ] [ opclass [ ( opclass_parameter = value [, ... ] ) ] ] [ ASC | DESC ] [ NULLS { FIRST | LAST } ...
- IF NOT EXISTS是一个条件语句,当条件为真时执行创建数据库的操作。 3. PG DB NOT EXISTS语法还可以与其他条件、连接和过滤器一起使用,以更精确地检查数据库是否存在的情况。 例如,我们要检查所有具有特定前缀的数据库是否存在,可以使用以下语法: ``` SELECT datname FROM pg_database WHERE datname LIKE '...
CREATE [ UNIQUE ] INDEX [ CONCURRENTLY ] [ [ IF NOT EXISTS ] name ] ON table_name [ USING method ] ( { column_name | ( expression ) } [ COLLATE collation ] [ opclass ] [ ASC | DESC ] [ NULLS { FIRST | LAST } ] [, ...] ) [ WITH ( storage_parameter = value [, ......
CREATE[UNIQUE]INDEX[CONCURRENTLY][[ IF NOT EXISTS]name ]ON[ONLY]table_name[USING method]( { column_name|( expression ) }[COLLATE collation][opclass [ ( opclass_parameter = value [, ...]) ] ][ASC | DESC][NULLS { FIRST | LAST }][, ...])[INCLUDE ( column_name [, ...]) ]...
4、解决方法 1)pg_dump导出时,没有选项使导出的语句中带if not exists,不能使之不存在时再创建或插入。 2)保证没有业务连接数据库时才导入,或向一个干净的数据库进行导入
【被测功能】: create schema 【测试类型】: 【数据库版本】(查询命令: gaussdb -V): 【预置条件】: --创建PG兼容模式 【操作步骤】(请填写详细的操作步骤): CREATE ROLE test1 IDENTIFIED BY 'Aa123456'; create schema if not exists test1 AUTHORIZATION test1; ...
PostgreSQL 出现“could not write to temporary file: No space left on device” 的错误,可能是临时文件夹磁盘空间不足。 在使用 pg_dump 备份数据库时出现“pg_dump: [archiver (db)] connection to database “数据库名” failed: could not connect to server: Connection refused” 的错误,可能是备份用户...
end if; else if(Lower(data_type)='varchar')then -- case to test whether it's varchar to give it the length property query := 'ALTER TABLE items.' || target_table_name || ' ADD COLUMN IF NOT EXISTS ' || added_column || ' ' || data_type || '(' || new.data...
query('CREATE EXTENSION IF NOT EXISTS vector'); Register the types for a client import pgvector from 'pgvector/pg'; await pgvector.registerTypes(client); or a pool pool.on('connect', async function (client) { await pgvector.registerTypes(client); }); Create a table await client.query(...
PG数据库和应用之间常见的部件有连接池、负载平衡组件、路由、防火墙等。我们常常不在意或者认为涉及的网络...