/** @pre SqlTypeUtil.sameNamedType(argTypes[0], (argTypes[1])) */
public RelDataType inferReturnType(SqlOperatorBinding opBinding) {
final RelDataType argType0 = opBinding.getOperandType(0);
final RelDataType argType1 = opBinding.getOperandType(1);
if (!(SqlTypeUtil.inCharOrBinaryFamilies(argType0)
&& SqlTypeUtil.inCharOrBinaryFamilies(argType1))) {
Util.pre(
SqlTypeUtil.sameNamedType(argType0, argType1),
"SqlTypeUtil.sameNamedType(argTypes[0], argTypes[1])");
}
SqlCollation pickedCollation = null;
if (SqlTypeUtil.inCharFamily(argType0)) {
if (!SqlTypeUtil.isCharTypeComparable(opBinding.collectOperandTypes().subList(0, 2))) {
throw opBinding.newError(
RESOURCE.typeNotComparable(
argType0.getFullTypeString(), argType1.getFullTypeString()));
}
pickedCollation =
SqlCollation.getCoercibilityDyadicOperator(
argType0.getCollation(), argType1.getCollation());
assert null != pickedCollation;
}
// Determine whether result is variable-length
SqlTypeName typeName = argType0.getSqlTypeName();
if (SqlTypeUtil.isBoundedVariableWidth(argType1)) {
typeName = argType1.getSqlTypeName();
}
RelDataType ret;
ret =
opBinding
.getTypeFactory()
.createSqlType(typeName, argType0.getPrecision() + argType1.getPrecision());
if (null != pickedCollation) {
RelDataType pickedType;
if (argType0.getCollation().equals(pickedCollation)) {
pickedType = argType0;
} else if (argType1.getCollation().equals(pickedCollation)) {
pickedType = argType1;
} else {
throw Util.newInternal("should never come here");
}
ret =
opBinding
.getTypeFactory()
.createTypeWithCharsetAndCollation(
ret, pickedType.getCharset(), pickedType.getCollation());
}
return ret;
}
private Expression castToAssignableValueImpl() {
if (requiresSpecializedCast()) {
if (rhsType.isNullable() && (!SqlTypeUtil.isDecimal(rhsType))) {
rhsExp = getValue(rhsType, rhsExp);
}
addStatement(
new ExpressionStatement(
new MethodCall(
lhsExp,
"cast",
new ExpressionList(rhsExp, Literal.makeLiteral(lhsType.getPrecision())))));
} else {
// Set current_date for casting time to timestamp. If
// rhsType is null then we may have to be ready for anything.
// But it will be null even for current_timestamp, so the
// condition below seems a bit excessive.
if ((lhsType.getSqlTypeName() == SqlTypeName.TIMESTAMP)
&& ((rhsType == null) || (rhsType.getSqlTypeName() == SqlTypeName.TIME))) {
addStatement(
new ExpressionStatement(
new MethodCall(lhsExp, "setCurrentDate", new ExpressionList(getCurrentDate()))));
}
addStatement(
new ExpressionStatement(
new MethodCall(
lhsExp, AssignableValue.ASSIGNMENT_METHOD_NAME, new ExpressionList(rhsExp))));
}
// Trim precision of datetime values.
//
if (((lhsType.getSqlTypeName() == SqlTypeName.TIMESTAMP)
|| (lhsType.getSqlTypeName() == SqlTypeName.TIME))) {
if ((rhsType != null)
// FIXME: JavaType(java.sql.Time) and
// JavaType(java.sql.Timestamp) say they support precision
// but do not.
&& !rhsType.toString().startsWith("JavaType(")
&& rhsType.getSqlTypeName().allowsPrec()
&& (lhsType.getPrecision() < rhsType.getPrecision())) {
int lhsPrecision = lhsType.getPrecision();
if (lhsPrecision == -1) {
lhsPrecision = 0;
}
addStatement(
new ExpressionStatement(
new MethodCall(
lhsExp,
SqlDateTimeWithoutTZ.ADJUST_PRECISION_METHOD_NAME,
new ExpressionList(Literal.makeLiteral(lhsPrecision)))));
}
}
boolean mayNeedPadOrTruncate = false;
if (SqlTypeUtil.inCharOrBinaryFamilies(lhsType) && !SqlTypeUtil.isLob(lhsType)) {
mayNeedPadOrTruncate = true;
}
if (mayNeedPadOrTruncate) {
// check overflow if it is datetime.
// TODO: should check it at the run time.
// so, it should be in the
// cast(SqlDateTimeWithTZ, int precision);
if ((rhsType != null) && (rhsType.getSqlTypeName() != null)) {
SqlTypeName typeName = rhsType.getSqlTypeName();
int precision = 0;
switch (typeName) {
case DATE:
precision = 10;
break;
case TIME:
precision = 8;
break;
case TIMESTAMP:
precision = 19;
break;
}
if ((precision != 0) && (precision > lhsType.getPrecision())) {
addStatement(
new IfStatement(
new BinaryExpression(
Literal.makeLiteral(precision),
BinaryExpression.GREATER,
Literal.makeLiteral(lhsType.getPrecision())),
getThrowStmtList()));
}
}
if ((rhsType != null)
&& (rhsType.getFamily() == lhsType.getFamily())
&& !SqlTypeUtil.isLob(rhsType)) {
// we may be able to skip pad/truncate based on
// known facts about source and target precisions
if (SqlTypeUtil.isBoundedVariableWidth(lhsType)) {
if (lhsType.getPrecision() >= rhsType.getPrecision()) {
// target precision is greater than source
// precision, so truncation is impossible
// and we can skip adjustment
return lhsExp;
}
} else {
if ((lhsType.getPrecision() == rhsType.getPrecision())
&& !SqlTypeUtil.isBoundedVariableWidth(rhsType)) {
// source and target are both fixed-width, and
// precisions are the same, so there's no adjustment
// needed
return lhsExp;
}
}
}
// determine target precision
Expression precisionExp = Literal.makeLiteral(lhsType.getPrecision());
// need to pad only for fixed width
Expression needPadExp = Literal.makeLiteral(!SqlTypeUtil.isBoundedVariableWidth(lhsType));
// pad character is 0 for binary, space for character
Expression padByteExp;
if (!SqlTypeUtil.inCharFamily(lhsType)) {
padByteExp = new CastExpression(OJSystem.BYTE, Literal.makeLiteral(0));
} else {
padByteExp = new CastExpression(OJSystem.BYTE, Literal.makeLiteral(' '));
}
// generate the call to do the job
addStatement(
new ExpressionStatement(
new MethodCall(
lhsExp,
BytePointer.ENFORCE_PRECISION_METHOD_NAME,
new ExpressionList(precisionExp, needPadExp, padByteExp))));
}
return lhsExp;
}