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 ...
In PostgreSQL, the user can convert the data stored in JSON objects (as key-value pairs) to a set of table rows. This operation can be performed by making use of thejson_to_recordset()function. Thejson_to_recordset()function takes a JSON array, which can contain one or more JSON objec...
Retrieving a Specific JSON Key as Text If you have a table named **eventsand you want to retrieve the value associated with the keynamefrom the JSON columnparams, you can use the following query: SELECTparams->>'name'FROMevents; This will return the value ofparams.nameas text from theeve...
PostgreSQL JSON examples Let’s take some examples of storing JSON data in the PostgreSQL database. 1) Storing JSON objects example First, create a new table called products: CREATE TABLE products( id SERIAL PRIMARY KEY, name VARCHAR(255) NOT NULL, properties JSONB ); The products table incl...
This is one of thePostgresjsonb query examples. The generalsyntaxfor creating a table in PostgreSQL with aJSONBcolumn is as follows: CREATE TABLE Table_Name( Column_name Datatype PRIMARY KEY, Column_name JSONB ); Elaborate the code
Let’s take a look at some more examples. Name/Value Pair JSON data is written as name/value pairs. A name/value pair is two values enclosed in quotes. This is an example of a name/value pair: "username": "jsmith" The name is “username” and the value is “jsmith”. They are...
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:
We use the following sample JSON data in our examples: { "metadata" : { "upperLastNameFirstName" : "ABC XYZ", "upperEmailAddress" : "abc@example.com", "profileType" : "P" }, "data" : { "onlineContactId" : "032323323", "displayName" : "Abc, Xyz", "firstName" :...
如果與queryTimeout都commandTimeout設定,queryTimeout則優先使用 。No 注意 結構描述和資料表名稱會區分大小寫。 在查詢中以""(雙引號) 括住它們。 範例: JSON "activities":[ {"name":"CopyFromPostgreSQL","type":"Copy","inputs": [ {"referenceName":"<PostgreSQL input dataset name>","type":"Data...
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...