postgres=#begin;BEGINpostgres=*#createtemptableaaa(c1int)oncommitpreserverows;CREATETABLEpostgres=*#insertintoaaavalues(1),(2);INSERT02postgres=*#commit;COMMITpostgres=#select*fromaaa;c1---12(2rows) 实现 接下来进入到比较有趣的数据库内核环节,关于temp table的实现链路 基本是和普通表的实现接近,包括...
复制 postgres=*# explainselectcount(*)frombmscantestwherea>1;QUERY PLAN---Finalize Aggregate(cost=1968.35..1968.36rows=1width=8)->Gather(cost=1568.33..1968.34rows=4width=8)Workers Planned:4->Partial Aggregate(cost=1568.33..1568.34rows=1width=8)->Parallel Seq Scanonbmscantest(cost=0.00..1547....
CREATE[TEMPORARY|TEMP]TABLEtable(columntype [NULL|NOTNULL] [UNIQUE] [DEFAULTvalue ] [column_constraint_clause |PRIMARYKEY} [ ... ] ] [, ... ] [,PRIMARYKEY(column[, ...] ) ] [,CHECK( condition ) ] [, table_constraint_clause ] ) [ INHERITS ( inherited_table [, ...] ) ]TEMPOR...
Create Table,Drop Table,ALTER TABLE等 CREATE[TEMPORARY|TEMP]TABLEtable(columntype[NULL|NOTNULL][UNIQUE][DEFAULTvalue][column_constraint_clause|PRIMARYKEY}[...]][,...][,PRIMARYKEY(column[,[,CHECK(condition)][,table_constraint_clause])[INHERITS(inherited_table[,...])]TEMPORARY此表只是为这次会话...
postgres=#\dbListoftablespacesName|Owner|Location---+---+---pg_default|postgres|pg_global|postgres|(2rows) 同时也可以通过操作系统命令查看相应的目录: -bash-4.2$ ls -l /var/lib/pgsql/11/data/ total 60 drwx---. 8 postgres postgres 80 Jan 8 05:...
CREATE[TEMPORARY|TEMP]TABLEtable(columntype [NULL|NOTNULL] [UNIQUE] [DEFAULTvalue ] [column_constraint_clause |PRIMARYKEY} [ ... ] ] [, ... ] [,PRIMARYKEY(column[, ...] ) ] [,CHECK( condition ) ] [, table_constraint_clause ] ) [ INHERITS ( inherited_table [, ...] ) ]TEMPOR...
gaussdb=# create temp table tmp1(a int,b int); NOTICE: The 'DISTRIBUTE BY' clause is not specified. Using round-robin as the distribution mode by default. HINT: Please use 'DISTRIBUTE BY' clause to specify suitable data distribution column. CREATE TABLE gaussdb=# insert into tmp1 values(...
create table t2 (like t1); mydb=# create table t2 (like t1); CREATE TABLE mydb=# \dt List of relations Schema | Name | Type | Owner ---+---+---+--- postgres | t | table | postgres postgres | t1 | table | postgres postgres | t2 | table | postgres...
How to Create a TEMPORARY Table Via the CREATE TABLE AS SELECT Command in Postgres? Use theTEMPkeyword along with theCREATE TABLE AScommand to create a temporary table in Postgres: CREATE TEMP TABLE tab_name AS SELECT col_list | expression ...
在当前数据库中创建一个新的空白表,该表由命令执行者所有。列存表支持的数据类型请参考列存表支持的数据类型。列存表不支持数组。列存表不支持生成列。列存表不支持创建全局临时表。创建列存表的数量建议不超过1000个。如果在建表过程中数据库系统发生故障,系统恢复后可能