sqlite::v2::json Namespace Reference

Classes
class	path_builder
	Helper for composing JSON path expressions compatible with SQLite's JSON1 dialect. More...

Functions
path_builder	path ()
	Convenience shortcut for starting a new JSON path builder rooted at $.
std::string	extract_expression (std::string_view json_expr, path_builder const &path)
	Produces a SQL expression that extracts a JSON value at the given path.
std::string	contains_expression (std::string_view json_expr, path_builder const &path, std::string_view value_expr)
	Produces a SQL expression that compares a JSON value at path with value_expr.
bool	available (connection &con)
	Detects whether the connected SQLite build exposes the JSON1 extension.
void	register_contains_function (connection &con, std::string_view function_name="json_contains_value")
	Registers a deterministic SQL scalar function that checks for JSON containment.

Function Documentation

available()

bool sqlite::v2::json::available

(

connection &

con

)

Detects whether the connected SQLite build exposes the JSON1 extension.

Returns

true when JSON functions (e.g. json_extract) can be executed, false otherwise.

contains_expression()

std::string sqlite::v2::json::contains_expression	(	std::string_view	json_expr,
		path_builder const &	path,
		std::string_view	value_expr )

Produces a SQL expression that compares a JSON value at path with value_expr.

This expands to json_extract(json_expr, path) = value_expr so it can be embedded inside WHERE clauses or CHECK constraints.

References path().

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extract_expression()

std::string sqlite::v2::json::extract_expression	(	std::string_view	json_expr,
		path_builder const &	path )

Produces a SQL expression that extracts a JSON value at the given path.

Parameters

json_expr	SQL expression that yields JSON text.
path	JSON path built with path_builder.

Returns

SQL snippet invoking json_extract(json_expr, path).

References path().

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path()

path_builder sqlite::v2::json::path ( )

inline

Convenience shortcut for starting a new JSON path builder rooted at $.

Definition at line 91 of file json_fts.hpp.

Referenced by contains_expression(), and extract_expression().

register_contains_function()

void sqlite::v2::json::register_contains_function	(	connection &	con,
		std::string_view	function_name = "json_contains_value" )

Registers a deterministic SQL scalar function that checks for JSON containment.

Parameters

con	Open connection that already enabled JSON1.
function_name	Optional SQL symbol name (defaults to json_contains_value).

Exceptions

database_exception

when JSON1 is unavailable or the function cannot be created.