例如,我使用以下函数将rows转换为PostgreSQL 9.2中的json select row_to_json(row(productid, product)) from gtab04; 这将返回低于结果的结果 row_to_json --- {"f1":3029,"f2":"DIBIZIDE M TAB"} {"f1":3026,"f2":"MELMET 1000 SR TAB"} {"f1":2715,"f2":"GLUCORE 浏览0提问于2014-08-29...
子查询必须只返回一列。这有点困难-你可以返回一个记录，但是如果你动态地构建它（例如，从选择的列中...
InetStringString MacaddrStringString Macaddr8StringString TsvectorStringString TsqueryStringString UUIDGuidGuid JsonStringString JsonbStringString ArrayStringString BitByte[]Byte[] Bit varyingByte[]Byte[] XMLStringString IntArrayStringString TextArrayStringString ...
( select count(*) from jsonb_array_elements ( jsonb_extract_path(test.json_msg , 'goods' ) ) as jae where jae::json->> 'id' in ('1001','1003') ) > 0 ; 1. 2. 3. 4. 输出: 效率还行: Total query runtime: 11 msec 检索到 2 行。 官方文档页: https://www.postgresql.org/...
postgres=#createindexidx_t_gin1_1ont_gin1usinggin (arr);CREATEINDEXpostgres=#explain(analyze,verbose,timing,costs,buffers)select*fromt_gin1wherearr &&array[1,2]; QUERY PLAN---Bitmap Heap Scanonpublic.t_gin1 (cost=8.93..121.24rows=185width=65) (actualtime=0.058..0.207rows=186loops=1) ...
PERFORM query; 通常被用来判断是否有记录,例如 PERFORM select 1 from tbl where xxx limit 1; if found then xxx else xxx end if; 执行返回单行的表达式或QUERY,并将结果存入变量。 SELECT select_expressions INTO [STRICT] target FROM ...; INSERT ... RETURNING expressions INTO [STRICT] target; ...
(Integer id){returnuserService.selectById(id);}@PostMapping("/insert")publicIntegerinsert(UserEntity userEntity){returnuserService.insert(userEntity);}@GetMapping("/pageQuery")publicPageInfo<UserEntity>pageQuery(@RequestParam("page")int page){int pageSize=3;returnuserService.pageQuery(page,page...
这是功能:public static function getList(){ $db = DbConnect::getDb(); $q = pg_query("SELECT u.usesysid as idUser, u.usename as login, u.passwd as password, ARRAY(SELECT b.rolname FROM pg_catalog.pg_auth_members m JOIN pg_catalog.pg_roles b ON (m.roleid = b.oid) WHERE m....
JsonNumber JsonObject JsonObjectConverter JsonParser JsonString JsonTokenizer SingleConverter SourceReader StringConverter StringLikeConverter TimeSpanConverter TokenReader UInt16Converter UInt32Converter UInt64Converter UriConverter XNodeArray Microsoft.Azure.PowerShell.Cmdlets.PostgreSql.Runtime.PowerShell ...
SELECTparams->'ids'->0FROMevents; This will return the first element of theidsarray from theparamscolumn in theeventstable. Filtering rows based on a nested JSON key Sometimes, your JSON might have nested structures. For instance, if you have a table nameduserswith a JSON columnpreferencesand...