@Override
public String visitLiteral(RexLiteral rexLiteral) {
Object v = rexLiteral.getValue();
RelDataType ty = rexLiteral.getType();
switch (rexLiteral.getTypeName()) {
case BOOLEAN:
return v.toString();
case CHAR:
return CompilerUtil.escapeJavaString(((NlsString) v).getValue(), true);
case NULL:
return "((" + ((Class<?>) typeFactory.getJavaClass(ty)).getCanonicalName() + ")null)";
case DOUBLE:
case BIGINT:
case DECIMAL:
switch (ty.getSqlTypeName()) {
case TINYINT:
case SMALLINT:
case INTEGER:
return Long.toString(((BigDecimal) v).longValueExact());
case BIGINT:
return Long.toString(((BigDecimal) v).longValueExact()) + 'L';
case DECIMAL:
case FLOAT:
case REAL:
case DOUBLE:
return Util.toScientificNotation((BigDecimal) v);
}
break;
default:
throw new UnsupportedOperationException();
}
return null;
}
/** @return true if all tuples match rowType; otherwise, assert on mismatch */
private boolean assertRowType() {
for (List<RexLiteral> tuple : tuples) {
assert tuple.size() == rowType.getFieldCount();
for (Pair<RexLiteral, RelDataTypeField> pair : Pair.zip(tuple, rowType.getFieldList())) {
RexLiteral literal = pair.left;
RelDataType fieldType = pair.right.getType();
// TODO jvs 19-Feb-2006: strengthen this a bit. For example,
// overflow, rounding, and padding/truncation must already have
// been dealt with.
if (!RexLiteral.isNullLiteral(literal)) {
assert (SqlTypeUtil.canAssignFrom(fieldType, literal.getType()));
}
}
}
return true;
}
/**
* Returns whether a node represents the NULL value.
*
* <p>Examples:
*
* <ul>
* <li>For {@link org.eigenbase.rex.RexLiteral} Unknown, returns false.
* <li>For <code>CAST(NULL AS <i>type</i>)</code>, returns true if <code>
* allowCast</code> is true, false otherwise.
* <li>For <code>CAST(CAST(NULL AS <i>type</i>) AS <i>type</i>))</code>, returns false.
* </ul>
*/
public static boolean isNullLiteral(RexNode node, boolean allowCast) {
if (node instanceof RexLiteral) {
RexLiteral literal = (RexLiteral) node;
if (literal.getTypeName() == SqlTypeName.NULL) {
assert (null == literal.getValue());
return true;
} else {
// We don't regard UNKNOWN -- SqlLiteral(null,Boolean) -- as
// NULL.
return false;
}
}
if (allowCast) {
if (node.isA(RexKind.Cast)) {
RexCall call = (RexCall) node;
if (isNullLiteral(call.operands[0], false)) {
// node is "CAST(NULL as type)"
return true;
}
}
}
return false;
}
/**
* Creates a call to the CAST operator, expanding if possible.
*
* @param type Type to cast to
* @param exp Expression being cast
* @return Call to CAST operator
*/
public RexNode makeCast(RelDataType type, RexNode exp) {
final SqlTypeName sqlType = type.getSqlTypeName();
if (exp instanceof RexLiteral) {
RexLiteral literal = (RexLiteral) exp;
Comparable value = literal.getValue();
if (RexLiteral.valueMatchesType(value, sqlType, false)
&& (!(value instanceof NlsString)
|| (type.getPrecision() >= ((NlsString) value).getValue().length()))
&& (!(value instanceof ByteString)
|| (type.getPrecision() >= ((ByteString) value).length()))) {
switch (literal.getTypeName()) {
case CHAR:
if (value instanceof NlsString) {
value = ((NlsString) value).rtrim();
}
break;
case TIMESTAMP:
case TIME:
final Calendar calendar = (Calendar) value;
int scale = type.getScale();
if (scale == RelDataType.SCALE_NOT_SPECIFIED) {
scale = 0;
}
calendar.setTimeInMillis(
SqlFunctions.round(
calendar.getTimeInMillis(), DateTimeUtils.powerX(10, 3 - scale)));
break;
case INTERVAL_DAY_TIME:
BigDecimal value2 = (BigDecimal) value;
final long multiplier =
literal.getType().getIntervalQualifier().getStartUnit().multiplier;
SqlTypeName typeName = type.getSqlTypeName();
// Not all types are allowed for literals
switch (typeName) {
case INTEGER:
typeName = SqlTypeName.BIGINT;
}
return makeLiteral(
value2.divide(BigDecimal.valueOf(multiplier), 0, BigDecimal.ROUND_HALF_DOWN),
type,
typeName);
}
return makeLiteral(value, type, literal.getTypeName());
}
} else if (SqlTypeUtil.isInterval(type) && SqlTypeUtil.isExactNumeric(exp.getType())) {
return makeCastExactToInterval(type, exp);
} else if (SqlTypeUtil.isExactNumeric(type) && SqlTypeUtil.isInterval(exp.getType())) {
return makeCastIntervalToExact(type, exp);
} else if (sqlType == SqlTypeName.BOOLEAN && SqlTypeUtil.isExactNumeric(exp.getType())) {
return makeCastExactToBoolean(type, exp);
} else if (exp.getType().getSqlTypeName() == SqlTypeName.BOOLEAN
&& SqlTypeUtil.isExactNumeric(type)) {
return makeCastBooleanToExact(type, exp);
}
return makeAbstractCast(type, exp);
}
/**
* Returns whether a node represents the NULL value or a series of nested CAST(NULL as <TYPE>)
* calls<br>
* For Example:<br>
* isNull(CAST(CAST(NULL as INTEGER) AS VARCHAR(1))) returns true
*/
public static boolean isNull(RexNode node) {
/* Checks to see if the RexNode is null */
return RexLiteral.isNullLiteral(node)
|| ((node.getKind() == RexKind.Cast) && isNull(((RexCall) node).operands[0]));
}
/** Variant of {@link #trimFields(RelNode, BitSet, Set)} for {@link ProjectRel}. */
public TrimResult trimFields(
ProjectRel project, BitSet fieldsUsed, Set<RelDataTypeField> extraFields) {
final RelDataType rowType = project.getRowType();
final int fieldCount = rowType.getFieldCount();
final RelNode input = project.getChild();
final RelDataType inputRowType = input.getRowType();
// Which fields are required from the input?
BitSet inputFieldsUsed = new BitSet(inputRowType.getFieldCount());
final Set<RelDataTypeField> inputExtraFields = new LinkedHashSet<RelDataTypeField>(extraFields);
RelOptUtil.InputFinder inputFinder =
new RelOptUtil.InputFinder(inputFieldsUsed, inputExtraFields);
for (Ord<RexNode> ord : Ord.zip(project.getProjects())) {
if (fieldsUsed.get(ord.i)) {
ord.e.accept(inputFinder);
}
}
// Create input with trimmed columns.
TrimResult trimResult = trimChild(project, input, inputFieldsUsed, inputExtraFields);
RelNode newInput = trimResult.left;
final Mapping inputMapping = trimResult.right;
// If the input is unchanged, and we need to project all columns,
// there's nothing we can do.
if (newInput == input && fieldsUsed.cardinality() == fieldCount) {
return new TrimResult(project, Mappings.createIdentity(fieldCount));
}
// Some parts of the system can't handle rows with zero fields, so
// pretend that one field is used.
if (fieldsUsed.cardinality() == 0) {
final Mapping mapping = Mappings.create(MappingType.InverseSurjection, fieldCount, 1);
final RexLiteral expr =
project.getCluster().getRexBuilder().makeExactLiteral(BigDecimal.ZERO);
RelDataType newRowType =
project
.getCluster()
.getTypeFactory()
.createStructType(
Collections.singletonList(expr.getType()), Collections.singletonList("DUMMY"));
ProjectRel newProject =
new ProjectRel(
project.getCluster(),
project.getCluster().traitSetOf(RelCollationImpl.EMPTY),
newInput,
Collections.<RexNode>singletonList(expr),
newRowType,
project.getFlags());
return new TrimResult(newProject, mapping);
}
// Build new project expressions, and populate the mapping.
List<RexNode> newProjectExprList = new ArrayList<RexNode>();
final RexVisitor<RexNode> shuttle = new RexPermuteInputsShuttle(inputMapping, newInput);
final Mapping mapping =
Mappings.create(MappingType.InverseSurjection, fieldCount, fieldsUsed.cardinality());
for (Ord<RexNode> ord : Ord.zip(project.getProjects())) {
if (fieldsUsed.get(ord.i)) {
mapping.set(ord.i, newProjectExprList.size());
RexNode newProjectExpr = ord.e.accept(shuttle);
newProjectExprList.add(newProjectExpr);
}
}
final RelDataType newRowType =
project
.getCluster()
.getTypeFactory()
.createStructType(Mappings.apply3(mapping, rowType.getFieldList()));
final List<RelCollation> newCollations =
RexUtil.apply(inputMapping, project.getCollationList());
final RelNode newProject;
if (RemoveTrivialProjectRule.isIdentity(
newProjectExprList, newRowType, newInput.getRowType())) {
// The new project would be the identity. It is equivalent to return
// its child.
newProject = newInput;
} else {
newProject =
new ProjectRel(
project.getCluster(),
project
.getCluster()
.traitSetOf(
newCollations.isEmpty() ? RelCollationImpl.EMPTY : newCollations.get(0)),
newInput,
newProjectExprList,
newRowType,
project.getFlags());
assert newProject.getClass() == project.getClass();
}
return new TrimResult(newProject, mapping);
}
/** Converts an expression from {@link RexNode} to {@link SqlNode} format. */
SqlNode toSql(RexProgram program, RexNode rex) {
if (rex instanceof RexLocalRef) {
final int index = ((RexLocalRef) rex).getIndex();
return toSql(program, program.getExprList().get(index));
} else if (rex instanceof RexInputRef) {
return field(((RexInputRef) rex).getIndex());
} else if (rex instanceof RexLiteral) {
final RexLiteral literal = (RexLiteral) rex;
switch (literal.getTypeName().getFamily()) {
case CHARACTER:
return SqlLiteral.createCharString((String) literal.getValue2(), POS);
case NUMERIC:
case EXACT_NUMERIC:
return SqlLiteral.createExactNumeric(literal.getValue().toString(), POS);
case APPROXIMATE_NUMERIC:
return SqlLiteral.createApproxNumeric(literal.getValue().toString(), POS);
case BOOLEAN:
return SqlLiteral.createBoolean((Boolean) literal.getValue(), POS);
case DATE:
return SqlLiteral.createDate((Calendar) literal.getValue(), POS);
case TIME:
return SqlLiteral.createTime(
(Calendar) literal.getValue(), literal.getType().getPrecision(), POS);
case TIMESTAMP:
return SqlLiteral.createTimestamp(
(Calendar) literal.getValue(), literal.getType().getPrecision(), POS);
case ANY:
switch (literal.getTypeName()) {
case NULL:
return SqlLiteral.createNull(POS);
// fall through
}
default:
throw new AssertionError(literal + ": " + literal.getTypeName());
}
} else if (rex instanceof RexCall) {
final RexCall call = (RexCall) rex;
final SqlOperator op = call.getOperator();
final List<SqlNode> nodeList = toSql(program, call.getOperands());
if (op == SqlStdOperatorTable.CAST) {
RelDataType type = call.getType();
if (type.getSqlTypeName() == SqlTypeName.VARCHAR
&& dialect.getDatabaseProduct() == SqlDialect.DatabaseProduct.MYSQL) {
// MySQL doesn't have a VARCHAR type, only CHAR.
nodeList.add(
new SqlDataTypeSpec(
new SqlIdentifier("CHAR", POS), type.getPrecision(), -1, null, null, POS));
} else {
nodeList.add(toSql(type));
}
}
if (op == SqlStdOperatorTable.CASE) {
final SqlNode valueNode;
final List<SqlNode> whenList = Expressions.list();
final List<SqlNode> thenList = Expressions.list();
final SqlNode elseNode;
if (nodeList.size() % 2 == 0) {
// switched:
// "case x when v1 then t1 when v2 then t2 ... else e end"
valueNode = nodeList.get(0);
for (int i = 1; i < nodeList.size() - 1; i += 2) {
whenList.add(nodeList.get(i));
thenList.add(nodeList.get(i + 1));
}
} else {
// other: "case when w1 then t1 when w2 then t2 ... else e end"
valueNode = null;
for (int i = 0; i < nodeList.size() - 1; i += 2) {
whenList.add(nodeList.get(i));
thenList.add(nodeList.get(i + 1));
}
}
elseNode = nodeList.get(nodeList.size() - 1);
return op.createCall(
POS,
valueNode,
new SqlNodeList(whenList, POS),
new SqlNodeList(thenList, POS),
elseNode);
}
if (op instanceof SqlBinaryOperator && nodeList.size() > 2) {
// In RexNode trees, OR and AND have any number of children;
// SqlCall requires exactly 2. So, convert to a left-deep binary tree.
return createLeftCall(op, nodeList);
}
return op.createCall(new SqlNodeList(nodeList, POS));
} else {
throw new AssertionError(rex);
}
}
