JSON Query Syntax and Examples PostgreSQL provides two JSON data types: json (non-validated) and jsonb (binary, optimized for indexing and querying). The jsonb type is generally preferred for querying because it supports indexing and efficient storage. Example 1: Querying a JSON Field Assume you...
selectdescription::json->'data'->(JSON_ARRAY_LENGTH(description::json->'data')-1)->0asreadtimefromleanheat.lh_demo_ecl_aggregatedata Examples of json operation(增删改查):fromhere CREATETABLEleanheat.TActivity ( idbigintPRIMARYKEY,--活动idtitlecharactervarying(128)NOTNULL,--活动名称pricepackage ...
SQL 语言：熟练掌握 SQL（Structured Query Language），包括数据定义语言（DDL），如 CREATE、ALTER、DROP 等语句，用于创建和修改数据库对象；数据操作语言（DML），如 SELECT、INSERT、UPDATE、DELETE 等语句，用于对数据进行查询和修改；以及数据控制语言（DCL），如 GRANT、REVOKE 等语句，用于管理数据库的权限。事务...
values("number", "requirements") <QuerySet [{'number': 102, 'requirements': [ {'parking': False, 'sea_view': True, 'double_bed': False}, {'parking': True, 'double_bed': True} ]}]> Deprecated since version 5.2: The ordering keyword argument is deprecated. Use JSONBAgg.order_by...
We can understand the workings of thejsonb_typeof()function using some examples. Example 1: Understanding the jsonb_typeof() Function in PostgreSQL To learn, how thejsonb_typeof()function works, we can execute the following query:
POST / HTTP/1.1 Host: postgres.tencentcloudapi.com Content-Type: application/json X-TC-Action: CreateDBInstances <公共请求参数> { "InstanceCount": "1", "AutoRenewFlag": "1", "Zone": "ap-guangzhou-5", "DBVersion": "12.4", "Storage": "10", "Period": "1", "SpecCode": "cdb.pg...
POST / HTTP/1.1 Host: postgres.tencentcloudapi.com Content-Type: application/json X-TC-Action: CreateInstances <公共请求参数> { "InstanceCount": "1", "AutoRenewFlag": "1", "AdminName": "test2313", "Zone": "ap-guangzhou-2", "AdminPassword": " xxxxxxx", "DBVersion": "12.4", "DB...
That query can use the GiST index from the exclusion constraint we created above. If all the above is wrong, should we use JSON in PostgreSQL at all? Don't get me wrong: JSON support in PostgreSQL is a wonderful thing. It is just that many people don't understand how to use it righ...
No (if "query" in activity source is specified) Example JSON Copy { "name": "PostgreSQLDataset", "properties": { "type": "PostgreSqlV2Table", "linkedServiceName": { "referenceName": "<PostgreSQL linked service name>", "type": "LinkedServiceReference" }, "annotations": [], "schema"...
public Object query() Get the query property: Database query. Type: string (or Expression with resultType string). Returns: the query value. toJson public JsonWriter toJson(JsonWriter jsonWriter) Overrides: PostgreSqlSource.toJson(JsonWriter jsonWriter) Parameters: jsonWriter Throws: IOExcepti...