public SqlExpression Translate(SqlExpression instance, MethodInfo method, IReadOnlyList <SqlExpression> arguments)
{
if (!(method.Equals(SubstringOnlyStartMethod) || method.Equals(SubstringStartAndLengthMethod)))
{
return(null);
}
var fromExpression = _fbSqlExpressionFactory.Add(arguments[0], _fbSqlExpressionFactory.Constant(1));
var forExpression = arguments.Count == 2 ? arguments[1] : null;
return(_fbSqlExpressionFactory.Substring(instance, fromExpression, forExpression));
}