Creates a new GValue which represents the SQL value given as argument. This is
the opposite of the function gda.data_handler.DataHandler.getSqlFromValue. The type argument
is used to determine the real data type requested for the returned value.
If the sql string is null, then the returned GValue is of type GDA_TYPE_NULL;
if the sql string does not correspond to a valid SQL string for the requested type, then
the null is returned.
Creates a new GValue which represents the SQL value given as argument. This is the opposite of the function gda.data_handler.DataHandler.getSqlFromValue. The type argument is used to determine the real data type requested for the returned value.
If the sql string is null, then the returned GValue is of type GDA_TYPE_NULL; if the sql string does not correspond to a valid SQL string for the requested type, then the null is returned.