BIT_AND:对一列或多列的位值进行按位与操作。 BIT_OR:对一列或多列的位值进行按位或操作。 BOOL_AND:对布尔列的值进行逻辑与操作。 BOOL_OR:对布尔列的值进行逻辑或操作。 EVERY:检查所有输入行的布尔条件是否都为真。 JSON_AGG:将多行数据聚合成一个 JSON 数组。 JSONB_AGG:将多行数据聚合成一个 JS...
23 + CASE WHEN MAX(coalesce(s.null_frac,0)) > 0 THEN ( 7 + count(s.attname) ) / 8 ELSE 0::int END + CASE WHEN bool_or(att.attname = 'oid' and att.attnum < 0) THEN 4 ELSE 0 END AS tpl_hdr_size, sum( (1-coalesce(s.null_frac, 0)) * coalesce(s.avg_width, 0) ...
SQL> create or replace directory BLOBDIR as 'D:/oradata/Pic'; Directory created. SQL> grant read on directory BLOBDIR to eygle; Grant succeeded. SQL> 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. ...
CREATEORREPLACEFUNCTION message_deletes(ids"varchar", userid int8) RETURNS int4AS $BODY$ DECLARE r RECORD; del bool; num int4 := 0; sql"varchar"; BEGIN sql :='select id,receiveuserid,senduserid,senddelete,receivedelete from message where id in (' || ids ||')'; FOR rINEXECUTE sq...
/* tag identifying scan/join method */953954RelOptInfo *parent;/* the relation this path can build */955PathTarget *pathtarget;/* list of Vars/Exprs, cost, width */956957ParamPathInfo *param_info;/* parameterization info, or NULL if none */958959boolparallel_aware;/* engage parallel-...
*/booltakenDuringRecovery;/* recovery-shaped snapshot? */boolcopied;/* false if it's a static snapshot */CommandId curcid;/* in my xact, CID < curcid are visible */uint32 speculativeToken; uint32 active_count;/* refcount on ActiveSnapshot stack,在活动快照链表里的 ...
背景在主流的OLTP数据库产品中,毫无疑问,PostgreSQL已经具备非常强大的竞争力(性能、功能、稳定性、成熟度、案例、跨行业应用等)。通过这些文章我们可以了解更细致的情况。《数据库十八摸 - 致 架构师、开发者》《数据库界的华山论剑 tpc.org》《PostgreSQL 前世今生》
\1. 赋值: PL/pgSQL中赋值语句的形式为:identIFier := expression，等号两端的变量和表达式的类型或者...
yes. it might be more appropriate to return a bool then. Sorry, something went wrong. devnexenforce-pushedthepg_set_chunked_rows_modebranch fromccb8fb8toc4e9aedCompareJune 15, 2024 17:33 GirgiasreviewedJun 15, 2024 View reviewed changes ...
Die gesuchte CASE-Anweisung stellt Bedingungsausführungen basierend auf der Wahrheit von booleschen Ausdrücken bereit. Jede WHEN-Klausel boolean-expression wird nacheinander ausgewertet, bis eine gefunden wird, die den Wert true ergibt. Anschließend werden die entsprechenden Anweisungen ausg...