4 PARALLEL_ENABLE AGGREGATE USING string_agg_type; 5 / Function created. 另外还有一种方法就是用oracle 10g增加的sys_connect_by_path来做,但是性能不好。 首先来准备测试数据,创建一个数据量是3倍的DBA_OBJECTS的表T。 SQL> drop table t; Table dropped. SQL> create table t 2 as select MOD(rownum...
LISTAGG operates on all rows and returns a single output row. ■ As a group-set aggregate, the function operates on and returns an output row for each group defined by the GROUP
PARALLEL_ENABLE AGGREGATE USING strcat_type; TYPE: create or replace type strcat_type as object ( cat_string varchar2(4000), static function ODCIAggregateInitialize(cs_ctx In Out strcat_type) return number, member function ODCIAggregateIterate(self In Out strcat_type,value in varchar2) return nu...
MogDB中的wm_concat、string_agg、listagg都可以实现类似oracle 中的wm_concat函数功能。 MogDB=# CREATE OR REPLACE FUNCTION pg_catalog.my_wm_concat_state_func (results text, val text) MogDB-# RETURNS text MogDB-# LANGUAGE sql COST 50 IMMUTABLE MogDB-# AS $$ select results || ',' ||val; $...
该方法是在方法2的基础上,使用动态SQL,将表名和字段名称传入,从而达到灵活的目的。 create or replace function str_list2( key_name in varchar2, key in varchar2, coname in varchar2, tname in varchar2 ) return varchar2 as type rc is ref cursor; ...
PostgreSQL , Oracle , PL/SQL , 聚合函数 , 自定义聚合函数 背景 Oracle的自定义聚合函数的定义方法,在创建函数是,使用AGGREGATE USING Clause关键词。 AGGREGATE USING Clause Specify AGGREGATE USING to identify this function as an aggregate function, or one that evaluates a group of rows and returns a...
sql clone "alter system set spfile= ''/oracle/app/oracle/product/11.2.0/db/dbs/spfileDGPHY1.ora''"; } executing Memory Script Starting backup at 2016-02-18 14:29:41 allocated channel: ORA_DISK_1 channel ORA_DISK_1: SID=71 instance=DGPRI1 device type=DISK Finished backup at 2016-02...
SQL> show parameter control NAME TYPE VALUE --- --- --- control_file_record_keep_time integer 7 control_files string /opt/oracle/oradata/cq/control 01.ctl, /opt/oracle/oradata/cq /control02.ctl, /opt/oracle/or adata/cq/control03.ctl --查看redo log大小和位置 set linesize 999 col...
SQL>selectname,valuefromv$diag_info;输出的信息如下图所示：在参数Diag Trace所对应的目录/u01/app/...
$$languagesqlcalledonnullinput;createAGGREGATEWMSYS.wm_concat (text) (sfunc=WMSYS.sf_concat,stype=text); 测试: postgres=# select reltype,wmsys.wm_concat(relname) from pg_class group by reltype order by reltype;reltype | wm_concat