Json path expression
A JSON path expression identifies locations in JSON data and can navigate, select, or filter objects and array elements.
100 SQL Server Mistakes and How to Avoid Them
A JSON path is an expression that identifies a location within a JSON document, including object properties and array elements.
- How it is used
- Locates JSON properties and array elements while generating, updating, or shredding JSON in SQL queries.
- How deep it goes
- Explains root notation, object hierarchy, array indexes, and nested-column mapping, but does not develop broader path syntax.
- Examples
- Uses an EmployeeAddress array containing employee identity and nested address fields.
- What you can do after
- Apply JSON paths via JSON_VALUE and OPENJSON to identify records, extract values, and return typed relational columns.
Read how 100 SQL Server Mistakes and How to Avoid Them explains json path expression →
Just Use Postgres!
SQL/JSON path language is a standardized language for navigating and filtering JSON data within SQL expressions.
- How it is used
- Retrieves and filters values in nested PostgreSQL JSON data for operational reports and targeted order queries.
- How deep it goes
- Builds paths from $, accessors, arrays, and filters, while deferring a complete treatment of every operator.
- Examples
- Demonstrates pizza-type counts, cheese-array queries, sausage filters, and chained conditions on custom pizzas.
- What you can do after
- Apply it via PostgreSQL JSONB functions to extract fields, inspect arrays, and filter multilevel JSON structures.
Related concepts
- jsonb_path_queryused by · jsonb_path_query is a PostgreSQL function that evaluates a JSON path against a jsonb value and returns the matching JSON items.
- jsonb_path_existsused by · jsonb_path_exists is a PostgreSQL function that returns whether a JSON path produces at least one result for a jsonb value.
- json_valueused by · JSON_VALUE is a SQL Server function that extracts a scalar value from a JSON document at a specified path.
- JSON objectuses · A JSON object is an unordered collection of members, each consisting of a string name paired with a JSON value, represented within curly braces.
These guides are generated from the text of Manning books by Manning's knowledge graph and link to the sections they draw on. The full books are available on liveBook and at manning.com.