Returning a Set of JSONB Objects in PostgreSQL Using jsonb_agg()

In PostgreSQL, you can use the jsonb_agg() function to aggregate multiple JSONB objects into a single JSONB array and return a set of JSONB objects from a database table.

Syntax and Usage:

To return a set of JSONB objects, you can use the following syntax:

SELECT jsonb_agg(jsonb_column) FROM mytable;

To group the results by a certain column and return a set of JSONB objects for each group, you can use the following syntax:

SELECT group_column, jsonb_agg(jsonb_column) FROM mytable GROUP BY group_column;

Note that the jsonb_agg() function is specific to PostgreSQL and may not be available in other database management systems. Additionally, PostgreSQL has a limit of 1GB for the jsonb data type, so you should be cautious when using this function with large amounts of data.

Using jsonb_agg() with Other Functions:

You can also use the jsonb_agg() function with other functions to aggregate data in more complex ways. For example, you can use the jsonb_build_object() function to create a JSONB object from a key-value pair and then use the jsonb_agg() function to aggregate multiple JSONB objects into a single JSONB array. Here’s an example:

 SELECT jsonb_agg(jsonb_build_object('name', name, 'age', age)) FROM mytable;

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