More examples and documentation here and here. WHERE CAST(properties->'amount' AS integer) > 0Īverage screen resolution SELECT AVG(CAST(browser->'resolution'->'x' AS integer)) AS width,ĪVG(CAST(browser->'resolution'->'y' AS integer)) AS height Total revenue per visitor: SELECT visitor_id, SUM(CAST(properties->'amount' AS integer)) AS total Lets see browser usage: SELECT browser->'name' AS browser, If the expression matches the queried JSON data, the corresponding JSON item, or set of items, is returned. The jsonbextractpathtext is a Postgres function that is equivalent to the > operator (please check the Postgres documentation linked earlier for more details). JSON query functions and operators pass the provided path expression to the path engine for evaluation. You have the full might of an RDBMS at your disposal. In PostgreSQL, path expressions are implemented as the jsonpath data type and can use any elements described in Section 8.14.7. Using the JSON operators, combined with traditional PostgreSQL aggregate functions, we can pull out whatever we want. This means for the attribute of username, the value is jsmith. The name is username and the value is jsmith. This is an example of a name/value pair: 'username': 'jsmith'. A name/value pair is two values enclosed in quotes. If any parameter is NULL, the jsonbpathquery () function will return NULL. JSON data is written as name/value pairs. JSON operators + PostgreSQL aggregate functions The PostgreSQL jsonbpathquery () function returns a set of JSONB values that contains all the values in the specified JSON value that match the specified path. Now lets select everything: SELECT * FROM events Populating the DB INSERT INTO books(client, data) values ( #2 I can't get the nested condition work (3rd AND in the sample request)Īccording to the examples in the documentation, the syntax looks OK but I have a syntax error that I don't understand.Example Creating a DB and a Table DROP DATABASE IF EXISTS books_db ĬREATE DATABASE books_db WITH ENCODING='UTF8' TEMPLATE template0 So I don't understand why we have a difference in the result That function may or may not be documented in its own right. Every operator has a function 'behind' it. Some operators are overloaded and will give more than one function, you have to look at the argument types to distinguish them.
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