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tds_empty_string_is_null option [database]

Controls whether empty strings are returned as NULL or a string containing one blank character for TDS connections.

On, Off

Off

By default, this option is set to Off and empty strings are returned as a string containing one blank character for TDS connections. When this option is set to On, empty strings are returned as NULL strings for TDS connections. Non-TDS connections distinguish empty strings from NULL strings.