string_agg(expression, delimiter) 简单的说string_agg函数能将结果集某个字段的所有行连接成字符串,并用指定delimiter分隔符分隔,expression表示要处理的字符类型数据;参数的类型为(text, text) 或 (bytea, bytea),函数返回的类型同输入参数类型一致,bytea属于二进制类型,使用情况不多,我们主要介绍text类型输入参数...
VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] ANALYZE [ table [ (column [, ...] ) ] ] VALUES 计算一个或一组行。 VALUES ( _expression_ [, ...] ) [, ...] [ ORDER BY _sort_expression_ [ ASC | DESC | USING _operator_ ] [, ...] ] [ LIMIT { _count_ | ALL } ] [ OFFSE...
mydb=>INSERTINTOuser_logins(user_name,login_cnt)VALUES('matiler',1),('francs',1);ERROR: duplicatekeyvalue violatesuniqueconstraint"user_logins_pkey"DETAIL:Key(user_name)=(francs) already exists. 1. 2. 3. 上述SQL试图插入两条数据,其中matiler这条数据不违反主键冲突,而francs这条数据违反主键冲...
$ export PG_CONNECTION_STRING="your_postgresql_connection_string" 您还需要 OpenAI API 密钥。前往platform.openai.com获取一个。获取后,也将其保存在环境变量中。 $ export OPENAI_API_KEY="{API_KEY}" 现在您可以使用psql以如下方式连接: PGOPTIONS="-c ai.openai_api_key=$OPENAI_API_KEY" psql -d $...
| VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12) + |RETURNING id (5rows) openGauss=#selectdb_name,unique_query_id,count(*)fromstatement_history group by db_name,unique_query_id order by3; db_name| unique_query_id |count---+---+---gzdz|1587254874|...
修改一个数据库。 ALTERDATABASEnameSETparameter{TO|=}{value|DEFAULT}ALTERDATABASEnameRESETparameterALTERDATABASEnameRENAMETOnew_nameALTERDATABASEnameOWNERTOnew_owner 复制 ALTER DEFAULT PRIVILEGES 定义默认的访问权限。 ALTERDEFAULTPRIVILEGES[FOR{ROLE|USER}target_role[,...]][INSCHEMAschema_name[,...]]ab...
CREATE [ UNIQUE ] INDEX name ON table [ USING method ] ( { column | ( expression ) } [ opclass ] [, ...] ) [ TABLESPACE tablespace ] [ WHERE predicate ] CREATE LANGUAGE 定义一种新的过程语言。 CREATE [ TRUSTED ] [ PROCEDURAL ] LANGUAGE name HANDLER call_handler [ VALIDATOR val_fu...
VALUES (1, 'Endangered species', 'Pandas are an endangered species', 1 ), (2, 'Freedom of Speech', 'Freedom of speech is a necessary right', 2), (3, 'Star Wars vs Star Trek', 'Few words from a big fan', 3); INSERT INTO posts_tags (post_id, tag_id) ...
VALUES ( _expression_ [, ...] ) [, ...] [ ORDER BY _sort_expression_ [ ASC | DESC | USING _operator_ ] [, ...] ] [ LIMIT { _count_ | ALL } ] [ OFFSET _start_ [ ROW | ROWS ] ] [ FETCH { FIRST | NEXT } [ _count_ ] { ROW | ROWS } ONLY ]更多内容可以参考...
$ export PG_CONNECTION_STRING="your_postgresql_connection_string"您还需要 OpenAI API 密钥。前往platform.openai.com 获取一个。获取后，也将其保存在环境变量中。$ export OPENAI_API_KEY="{API_KEY}"现在您可以使用 psql 以如下方式连接：PGOPTIONS="-c ai.openai_api_key=$OPENAI_API_KEY" psql -d $...