示例#1
0
func (e *Evaluator) handleComparisonOp(o *ast.BinaryOperationExpr) bool {
	a, b := types.Coerce(o.L.GetValue(), o.R.GetValue())
	if types.IsNil(a) || types.IsNil(b) {
		// for <=>, if a and b are both nil, return true.
		// if a or b is nil, return false.
		if o.Op == opcode.NullEQ {
			if types.IsNil(a) || types.IsNil(b) {
				o.SetValue(oneI64)
			} else {
				o.SetValue(zeroI64)
			}
		} else {
			o.SetValue(nil)
		}
		return true
	}

	n, err := types.Compare(a, b)
	if err != nil {
		e.err = errors.Trace(err)
		return false
	}

	r, err := getCompResult(o.Op, n)
	if err != nil {
		e.err = errors.Trace(err)
		return false
	}
	if r {
		o.SetValue(oneI64)
	} else {
		o.SetValue(zeroI64)
	}
	return true
}
示例#2
0
文件: binop.go 项目: nengwang/tidb
func (o *BinaryOperation) coerceArithmetic2(a interface{}, b interface{}) (x interface{}, y interface{}, err error) {
	x, err = o.coerceArithmetic(a)
	if err != nil {
		return
	}

	y, err = o.coerceArithmetic(b)
	if err != nil {
		return
	}

	x, y = types.Coerce(x, y)
	return x, y, nil
}
示例#3
0
文件: binop.go 项目: nengwang/tidb
func (o *BinaryOperation) get2(ctx context.Context, args map[interface{}]interface{}) (x, y interface{}, err error) {
	x, err = o.L.Eval(ctx, args)
	if err != nil {
		err = o.traceErr(err)
		return
	}
	y, err = o.R.Eval(ctx, args)
	if err != nil {
		err = o.traceErr(err)
		return
	}

	x, y = types.Coerce(x, y)
	return x, y, nil
}
示例#4
0
// See https://dev.mysql.com/doc/refman/5.7/en/control-flow-functions.html#function_nullif
func builtinNullIf(args []interface{}, m map[interface{}]interface{}) (interface{}, error) {
	// nullif(expr1, expr2)
	// returns null if expr1 = expr2 is true, otherwise returns expr1
	v1 := args[0]
	v2 := args[1]

	if v1 == nil || v2 == nil {
		return v1, nil
	}

	// coerce for later eval compare
	x, y := types.Coerce(v1, v2)

	if n, err := evalCompare(x, y); err != nil || n == 0 {
		return nil, err
	}

	return v1, nil
}
示例#5
0
func (e *Evaluator) handleArithmeticOp(o *ast.BinaryOperationExpr) bool {
	a, err := coerceArithmetic(o.L.GetValue())
	if err != nil {
		e.err = err
		return false
	}

	b, err := coerceArithmetic(o.R.GetValue())
	if err != nil {
		e.err = err
		return false
	}
	a, b = types.Coerce(a, b)

	if a == nil || b == nil {
		// TODO: for <=>, if a and b are both nil, return true
		o.SetValue(nil)
		return true
	}

	// TODO: support logic division DIV
	var result interface{}
	switch o.Op {
	case opcode.Plus:
		result, e.err = computePlus(a, b)
	case opcode.Minus:
		result, e.err = computeMinus(a, b)
	case opcode.Mul:
		result, e.err = computeMul(a, b)
	case opcode.Div:
		result, e.err = computeDiv(a, b)
	case opcode.Mod:
		result, e.err = computeMod(a, b)
	case opcode.IntDiv:
		result, e.err = computeIntDiv(a, b)
	default:
		e.err = errors.Errorf("invalid op %v in arithmetic operation", o.Op)
		return false
	}
	o.SetValue(result)
	return e.err == nil
}
示例#6
0
func (e *Evaluator) handleArithmeticOp(o *ast.BinaryOperationExpr) bool {
	a, err := coerceArithmetic(types.RawData(o.L.GetValue()))
	if err != nil {
		e.err = errors.Trace(err)
		return false
	}

	b, err := coerceArithmetic(types.RawData(o.R.GetValue()))
	if err != nil {
		e.err = errors.Trace(err)
		return false
	}

	a, b = types.Coerce(a, b)
	if a == nil || b == nil {
		o.SetValue(nil)
		return true
	}

	var result interface{}
	switch o.Op {
	case opcode.Plus:
		result, e.err = computePlus(a, b)
	case opcode.Minus:
		result, e.err = computeMinus(a, b)
	case opcode.Mul:
		result, e.err = computeMul(a, b)
	case opcode.Div:
		result, e.err = computeDiv(a, b)
	case opcode.Mod:
		result, e.err = computeMod(a, b)
	case opcode.IntDiv:
		result, e.err = computeIntDiv(a, b)
	default:
		e.err = ErrInvalidOperation.Gen("invalid op %v in arithmetic operation", o.Op)
		return false
	}
	o.SetValue(result)
	return e.err == nil
}
示例#7
0
func (e *Evaluator) handleBitOp(o *ast.BinaryOperationExpr) bool {
	a, b := types.Coerce(o.L.GetValue(), o.R.GetValue())

	if types.IsNil(a) || types.IsNil(b) {
		o.SetValue(nil)
		return true
	}

	x, err := types.ToInt64(a)
	if err != nil {
		e.err = errors.Trace(err)
		return false
	}

	y, err := types.ToInt64(b)
	if err != nil {
		e.err = errors.Trace(err)
		return false
	}

	// use a int64 for bit operator, return uint64
	switch o.Op {
	case opcode.And:
		o.SetValue(uint64(x & y))
	case opcode.Or:
		o.SetValue(uint64(x | y))
	case opcode.Xor:
		o.SetValue(uint64(x ^ y))
	case opcode.RightShift:
		o.SetValue(uint64(x) >> uint64(y))
	case opcode.LeftShift:
		o.SetValue(uint64(x) << uint64(y))
	default:
		e.err = ErrInvalidOperation.Gen("invalid op %v in bit operation", o.Op)
		return false
	}
	return true
}