func (v *typeInferrer) binaryOperation(x *ast.BinaryOperationExpr) {
switch x.Op {
case opcode.AndAnd, opcode.OrOr, opcode.LogicXor:
x.Type = types.NewFieldType(mysql.TypeLonglong)
case opcode.LT, opcode.LE, opcode.GE, opcode.GT, opcode.EQ, opcode.NE, opcode.NullEQ:
x.Type = types.NewFieldType(mysql.TypeLonglong)
case opcode.RightShift, opcode.LeftShift, opcode.And, opcode.Or, opcode.Xor:
x.Type = types.NewFieldType(mysql.TypeLonglong)
x.Type.Flag |= mysql.UnsignedFlag
case opcode.IntDiv:
x.Type = types.NewFieldType(mysql.TypeLonglong)
case opcode.Plus, opcode.Minus, opcode.Mul, opcode.Mod:
if x.L.GetType() != nil && x.R.GetType() != nil {
xTp := mergeArithType(x.L.GetType().Tp, x.R.GetType().Tp)
x.Type = types.NewFieldType(xTp)
leftUnsigned := x.L.GetType().Flag & mysql.UnsignedFlag
rightUnsigned := x.R.GetType().Flag & mysql.UnsignedFlag
// If both operands are unsigned, result is unsigned.
x.Type.Flag |= (leftUnsigned & rightUnsigned)
}
case opcode.Div:
if x.L.GetType() != nil && x.R.GetType() != nil {
xTp := mergeArithType(x.L.GetType().Tp, x.R.GetType().Tp)
if xTp == mysql.TypeLonglong {
xTp = mysql.TypeDecimal
}
x.Type = types.NewFieldType(xTp)
}
}
x.Type.Charset = charset.CharsetBin
x.Type.Collate = charset.CollationBin
}
