JSON_SCALAR

Syntax

Description of the illustration json_scalar.eps

Purpose

JSON_SCALAR accepts a SQL scalar value as input and returns a corresponding JSON scalar value as a JSON type instance. The value can be an Oracle-specific JSON-language type, such as a date, which is not part of the JSON standard.

To use JSON_SCALAR you must set the database initialization parameter compatible is at least 20. Otherwise it raises an error.

The argument to JSON_SCALAR can be an instance of any of these SQL data types: BINARY_DOUBLE, BINARY_FLOAT, BLOB, CLOB, DATE, INTERVAL YEAR TO MONTH, INTERVAL DAY TO SECOND, JSON, NUMBER, RAW, TIMESTAMP, VARCHAR, VARCHAR2, or VECTOR.

The returned JSON type instance is a JSON-language scalar value supported by Oracle.

If the argument to JSON_SCALAR is a SQL NULL value, then you can obtain a return value as follows:

SQL NULL, the default behavior
JSON null, using keywords NULL ON NULL
An empty JSON string, " ", using keywords EMPTY STRING ON NULL

The default behavior of returning SQL NULL is the only exception to the rule that a JSON scalar value is returned.