第一:列转行(对某列拆分,一列拆多行)lateral view explode(split(column, ',')) num数据 2122 9,12 2123 12,15 2124 12,15 2125 1,12,15 建表 create table if not exists t_row_to_column_tmp( id string, tag string ) row form
AI代码解释 CREATE[ORREPLACE]FUNCTIONname([[argmode][argname]argtype[{DEFAULT|=}default_expr][,...]])[RETURNSrettype|RETURNSTABLE(column_name column_type[,...])]{LANGUAGElang_name|TRANSFORM{FORTYPEtype_name}[,...]|WINDOW|IMMUTABLE|STABLE|VOLATILE|[NOT]LEAKPROOF|CALLEDONNULLINPUT|RETURNSNULLO...
*删除表中的字段: alter table [表名] drop column [字段名]; *重命名一个字段: alter table [表名] rename column [字段名A] to [字段名B]; *给一个字段设置缺省值: alter table [表名] alter column [字段名] set default [新的默认值]; *去除缺省值: alter table [表名] alter column [字段...
AI代码解释 CREATE[UNIQUE]INDEX[CONCURRENTLY][[IFNOTEXISTS]name]ON[ONLY]table_name[USINGmethod]({column_name|(expression)}[COLLATEcollation][opclass[(opclass_parameter=value[,...])]][ASC|DESC][NULLS{FIRST|LAST}][,...])[INCLUDE(column_name[,...])][WITH(storage_parameter[=value][,......
默认情况下,PostgreSQL 在创建对象时,不会将某些类型的对象的权限授予 PUBLIC:FOREIGN DATA WRAPPER、FOREIGN SERVER、LARGE OBJECT、PARAMETER、SCHEMA、SEQUENCE、TABLE 、Table column 及 TABLESPACE。 默认情况下,PostgreSQL 在创建对象时,会将某些类型的对象的权限授予 PUBLIC:DATABASE 【CONNECT 和 TEMPORARY(创建临时表...
ALTER MATERIALIZED VIEW [ IF EXISTS ] nameaction [, ... ]ALTER MATERIALIZED VIEW nameDEPENDS ON EXTENSION extension_nameALTER MATERIALIZED VIEW [ IF EXISTS ] nameRENAME [ COLUMN ] column_name TO new_column_nameALTER MATERIALIZED VIEW [ IF EXISTS ] nameSET SCHEMA new_schemaALTER MATERIALIZED VI...
{ FIRST | NEXT } [ count ] { ROW | ROWS } ONLY ] [ FOR { UPDATE | NO KEY UPDATE | SHARE | KEY SHARE } [ OF table_name [, ...] ] [ NOWAIT | SKIP LOCKED ] [...] ] from_item 可以是以下选项之一: [ ONLY ] table_name [ * ] [ [ AS ] alias [ ( column_alias [,...
select*fromwhere<column_name>>'Tom'collate"C"; 使用本土化索引进行排序 排序语句中的collate与索引的collate保持一致,才能使用这个索引进行排序。命令如下: createindex idxaon(<column_name>collate"en_US"); explainselect*fromorderby<column_name>collate"en_US"; 输出结果示例...
ALTER TABLE toast_t ALTER COLUMN vname SET STORAGE {PLAIN | EXTENDED | MAIN | EXTERNAL}; 示例: create table toast_t1(dd character varying); alter table toast_t1 alter column dd set storage main; /d+ toast_1 Column | Type | Storage | ...
test_schema|osdba(4rows)# 查看模式里的表t1的信息postgres=# \d schema2.t1;Table"schema2.t1"Column|Type|Modifiers ---+---+---id|integer|not null comments|character varying(50)|Indexes:"t1_pkey"PRIMARY KEY, btree(id) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12...