SELECT m.name FROM manufacturers m LEFT JOIN LATERAL get_product_names(m.id) pname ON true WHERE pname IS NULL; 1.2 WHERE 子句 WHERE子句的语法是: WHERE search_condition 这里的 ***search_condition\*** 是任意返回一个 boolean 类型值的值表达式(参阅值表达式)。 在完成对 FROM 子句的处理之...
CREATETABLEfoo (fooidint, foosubidint, fooname text);CREATEFUNCTIONgetfoo(int)RETURNSSETOF fooAS$$SELECT*FROMfooWHEREfooid=$1; $$LANGUAGESQL;SELECT*FROMgetfoo(1)ASt1;SELECT*FROMfooWHEREfoosubidIN(SELECTfoosubidFROMgetfoo(foo.fooid) zWHEREz.fooid=foo.fooid );CREATEVIEWvw_getfooASSELECT...
Operation ID: GetItems This operation gets rows from a table. Parameters 展開資料表 NameKeyRequiredTypeDescription Table name table True string Name of PostgreSQL table Filter Query $filter string An ODATA filter query to restrict the entries returned (e.g. stringColumn eq 'string' OR ...
postgresql 与sql_query的左连接中列名不明确会导致将错误的列Map到结构对于diesel::sql_query柴油机，按...
(1)首先exec_simple_query函数会将得到的SQL语句通过调用pg_parse_query进入词法和语法分析的主题处理过程,然后函数pg_parse_query调用词法和语法分析的入口函数raw_parse生成分析树。 raw_parse函数通过分词与语法引擎进行对SQL语句的识别,其中执行函数时会调用makeFuncCall,初始化FuncCall。这是执行函数所必须调用的。
oid | relname | relnamespace ---+---+--- 1259 | pg_class | 11 */ //打开pg_class表,这里是以行的排他锁打开这个文件 pg_class_desc = table_open(RelationRelationId, RowExclusiveLock); // 检查表中每个列的名称和数据类型 CheckAttributeNamesTypes(tupdesc, relkind, allow_system_table_mods...
Column aliases –learn how to assign temporary names to columns or expressions within a query. Order By –guide you on how to sort the result set returned by a query. Select Distinct –show you how to remove duplicate rows from the result set. Section 2. Filtering Data Where –filter rows...
postgres=# \set ECHO_HIDDEN on postgres=# \dt *** QUERY *** SELECT n.nspname as "Schema", c.relname as "Name", CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'm' THEN 'materialized view' WHEN 'i' THEN 'index' WHEN 'S' THEN 'sequence' WHEN 's' ...
LOWER_ATTRIBUTE_NAMES OBJECT OBJECT_TRANSFORM UPPER_ATTRIBUTE_NAMES 空间函数 AddBBox DropBBox GeometryType H3_Boundary H3_Center H3_FromLongLat H3_FromPoint H3_Polyfill ST_AddPoint ST_Angle ST_Area ST_AsBinary ST_AsEWKB ST_AsEWKT ST_AsGeoJSON ST_AsHexWKB ST_AsHexEWKB ST_AsText ST_Azimuth...
《PostgreSQL 17 preview - 增加GUC standby_slot_names , 保证这些standby已接收并flush所有逻辑slot向下游发送逻辑数据对应的WAL》 《PostgreSQL 17 preview - pg_createsubscriber支持将物理从库转换为逻辑从库》 《PostgreSQL 17 preview - 跟踪slot断联时间戳pg_replication_slots.inactive_since》 ...