比如下面 UPDATE 语句,MySQL 实际执行的还是嵌套子查询(DEPENDENT SUBQUERY),其执行时间可想而知。 explain extendedUPDATE operation oSET status = 'applying'WHERE o.id IN (SELECT id FROM (SELECT o.id,o.status FROM operation o WHERE o.group = 123 AND o.status NOT IN ('done') ORDER BY o.pare...
104 * node --- the Query structure is not used by the executor. 105 */106typedef struct Query107{108NodeTag type;109110CmdType commandType;/* select|insert|update|delete|utility */111112QuerySource querySource;/* where did I come from? */113114uint32 queryId;/* query identifier (can be...
with t1 as (select hos_series_instance_uid from public.hos_series_ct where hos_study_instance_uid='123' limit 1) update public.hos_series_ct SET upload_status=0 WHERE hos_series_instance_uid in (select * from t1)" 这样就能做到只更新一行数据。 WITH 查询的基础语法如下: WITH name_for_...
PGSQL基本操作语句 updatetable01setname='msq_all'whereid=122;--更新数据insertintotable01(id,dmcode,name,month)values(122,1,'app_all',201706) ;--插入数据SELECT*FROMtable01where1=1ORDERBYapp_name,flagasc/desc;--查询数据并且排序select*frompersons limit5offset0;--查询起点0开始查询,返回5条数据...
更改影响的表(只有INSERT,UPDATE和DELETE有) 4.条件 (qualification) WHERE 子句 5.连接树 JOIN表的条件和顺序 6.其他 如ORDER BY 等 视图是由规则系统实现的 PG中创建一个视图: createviewv_t1asselect*fromt1; 在内部,这句话实际上是这样操作的: ...
pgsql的类型对应java,PostgreSQL子查询子查询或称为内部查询、嵌套查询,指的是在PostgreSQL查询中的WHERE子句中嵌入查询语句。一个SELECT语句的查询结果能够作为另一个语句的输入值。子查询可以与SELECT、INSERT、UPDATE和DELETE语句一起使用,并可使用运算符如=、<、&
pgsql中常用的sql语句 2.插入数据(InsertInto):```INSERTINTOtable_name(column1,column2,...)VALUES(value1,value2,...);```3.查询数据(Select):```SELECTcolumn1,column2,...FROMtable_nameWHEREcondition;pgsql中常用的sql语句 4.更新数据(Update):```UPDATEtable_nameSETcolumn1=value1,column...
create table tb1 as (select *, row_number() over(order by name) as rownum from tb); //根据两张表共同的字段name,将tb1中rownum对应值更新到tb中num中 update tb set num=(select tb1.rownum from tb1 where tb.name = tb1.name); ...
CREATE OR REPLACE FUNCTION migrate_data(OUT row_ct int) LANGUAGE plpgsql AS $func$ BEGIN WITH sel AS ( SELECT id FROM tablea WHERE migrated = false ORDER BY id -- to proceed in deterministic order LIMIT 2000 FOR UPDATE -- only for concurrent write access ) , upd AS ( UPDATE tablea ...
('||LABEL||')' END FROM CNT_MEASUREMENT_TEMPLATE_SIZE WHERE PARENT_ID = MEASUREMENT_TEMPLATE.ID ORDER BY SEQ_NO),', ')); --- set sizes value for cnt_measurement_template whose sizes value is null or '' --- UPDATE CNT_MEASUREMENT_TEMPLATE SET SIZES = SIZES_VALUE WHERE ID = MEASURE...