INNER JOIN pg_index x ON c.oid = x.indrelid INNER JOIN pg_class i ON i.oid = x.indexrelid LEFT JOIN pg_namespace n ON n.oid = c.relnamespace WHERE c.relkind = ANY (ARRAY['r', 't']) and c.relname not like 'pg%';
PostgreSQL是一种开源的关系型数据库管理系统,支持广泛的数据类型和功能。GIN(Generalized Inverted Index)索引是PostgreSQL中的一种索引类型,用于加速对包含多个元素的列的查询。 当需要在PostgreSQL中使用GIN索引与ARRAY关键字一起时,可以按照以下步骤进行操作:
postgres=#dropindexidx_tbl_1;DROPINDEXpostgres=#createindexidx_tbl_1ontbl (gid);CREATEINDEXpostgres=#createindexidx_tbl_2ontblusinggin (c1); 实际效果比GIN的复合索引差一些 explain (analyze,verbose,timing,costs,buffers) select *fromtbl wheregid=1andc1 @> array[1,2,3]; explain (analyze,verb...
JOIN pg_class i ON i.oid=x.indexrelid LEFT JOIN pg_namespace n ON n.oid=c.relnamespace WHERE c.relkind=ANY(ARRAY['r','t']) AND c.relname LIKE'test1'; 6.查看索引的大小 这是一种非常简单的方法来获取PostgreSQL索引的大小,test1_id_index指建的索引名。 SELECT pg_size_pretty(pg_relati...
NOTICE: CREATE TABLE will create implicit sequence "test_array_id_seq" for serial column "test_array.id" NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "test_array_pkey" for table "test_array" CREATE TABLE mydb=> \d test_array ...
PostgreSQLPostgreSQL数据库index——索引类型简介 索引类型 PostgreSQL提供了如下类型的索引:B-tree、Hash、GiST、SP-GiST、GIN和BRIN。 B-Tree索引可以处理等号和范围查询某些能够排序的数据。特别地,PG查询计划器在索引的列涉及到如下比较运算符(<、<=、=、>=、>)会考虑使用B-Tree索引。构造等价于这些运算符的...
postgres=# create index idx_t_kenyon on t_kenyon using gin(items); CREATE INDEX postgres=# set enable_seqscan = off; postgres=# explain select * from t_kenyon where items@>array[2]; QUERY PLAN --- Bitmap Heap Scan on t_kenyon (cost=8.00..12.01 rows=1 width=36) Recheck Cond: (...
tb_index (name,phone) values (md5(random()::text || current_timestamp::text)::uuid,array[random()::varchar(64),random()::varchar(64)]); end loop; end; $$ language plpgsql; 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
i.relnameASindexname, t.spcnameAStablespace, pg_get_indexdef(i.oid)ASindexdefFROMpg_index xJOINpg_class cONc.oid=x.indrelidJOINpg_class iONi.oid=x.indexrelidLEFTJOINpg_namespace nONn.oid=c.relnamespaceLEFTJOINpg_tablespace tONt.oid=i.reltablespaceWHERE(c.relkind=ANY(ARRAY['r'::"char...
xmin; /* XID < xmin are visible to me /* DistributedTransactionId xmax; /* XID >= xmax are invisible to me /* int32 count; /* # of distributed xids in inProgressXidArray */ DistributedTransactionId *inProgressXidArray;} DistributedSnapshot;在这个结构中，分布式...