/**
* Creates a relational expression which projects an array of expressions, and optionally
* optimizes.
*
* <p>The result may not be a {@link ProjectRel}. If the projection is trivial, <code>child</code>
* is returned directly; and future versions may return other formulations of expressions, such as
* {@link CalcRel}.
*
* @param child input relational expression
* @param exprs list of expressions for the input columns
* @param fieldNames aliases of the expressions, or null to generate
* @param optimize Whether to return <code>child</code> unchanged if the projections are trivial.
*/
public static RelNode createProject(
RelNode child, List<RexNode> exprs, List<String> fieldNames, boolean optimize) {
final RelOptCluster cluster = child.getCluster();
final RexProgram program =
RexProgram.create(child.getRowType(), exprs, null, fieldNames, cluster.getRexBuilder());
final List<RelCollation> collationList = program.getCollations(child.getCollationList());
if (DeprecateProjectAndFilter) {
return new CalcRel(
cluster, child.getTraitSet(), child, program.getOutputRowType(), program, collationList);
} else {
final RelDataType rowType =
RexUtil.createStructType(cluster.getTypeFactory(), exprs, fieldNames);
if (optimize && RemoveTrivialProjectRule.isIdentity(exprs, rowType, child.getRowType())) {
return child;
}
return new ProjectRel(
cluster,
cluster.traitSetOf(
collationList.isEmpty() ? RelCollationImpl.EMPTY : collationList.get(0)),
child,
exprs,
rowType,
ProjectRelBase.Flags.Boxed);
}
}
/**
* Creates a relational expression which projects an array of expressions, and optionally
* optimizes.
*
* <p>The result may not be a {@link ProjectRel}. If the projection is trivial, <code>child</code>
* is returned directly; and future versions may return other formulations of expressions, such as
* {@link CalcRel}.
*
* @param child input relational expression
* @param exprs list of expressions for the input columns
* @param fieldNames aliases of the expressions, or null to generate
* @param optimize Whether to return <code>child</code> unchanged if the projections are trivial.
*/
public static RelNode createProject(
RelNode child, List<RexNode> exprs, List<String> fieldNames, boolean optimize) {
final RelOptCluster cluster = child.getCluster();
final RexProgram program =
RexProgram.create(child.getRowType(), exprs, null, fieldNames, cluster.getRexBuilder());
final List<RelCollation> collationList = program.getCollations(child.getCollationList());
if (DEPRECATE_PROJECT_AND_FILTER) {
return new CalcRel(
cluster, child.getTraitSet(), child, program.getOutputRowType(), program, collationList);
} else {
final RelDataType rowType =
RexUtil.createStructType(
cluster.getTypeFactory(),
exprs,
fieldNames == null
? null
: SqlValidatorUtil.uniquify(fieldNames, SqlValidatorUtil.F_SUGGESTER));
if (optimize && RemoveTrivialProjectRule.isIdentity(exprs, rowType, child.getRowType())) {
return child;
}
return new ProjectRel(
cluster,
cluster.traitSetOf(
collationList.isEmpty() ? RelCollationImpl.EMPTY : collationList.get(0)),
child,
exprs,
rowType,
ProjectRelBase.Flags.BOXED);
}
}
private Expression translate0(RexNode expr) {
if (expr instanceof RexInputRef) {
// TODO: multiple inputs, e.g. joins
final Expression input = getInput(0);
final int index = ((RexInputRef) expr).getIndex();
final List<RelDataTypeField> fields = program.getInputRowType().getFieldList();
final RelDataTypeField field = fields.get(index);
if (fields.size() == 1) {
return input;
} else if (input.getType() == Object[].class) {
return Expressions.convert_(
Expressions.arrayIndex(input, Expressions.constant(field.getIndex())),
Types.box(JavaRules.EnumUtil.javaClass(typeFactory, field.getType())));
} else {
return Expressions.field(input, field.getName());
}
}
if (expr instanceof RexLocalRef) {
return translate(program.getExprList().get(((RexLocalRef) expr).getIndex()));
}
if (expr instanceof RexLiteral) {
return Expressions.constant(
((RexLiteral) expr).getValue(), typeFactory.getJavaClass(expr.getType()));
}
if (expr instanceof RexCall) {
final RexCall call = (RexCall) expr;
final SqlOperator operator = call.getOperator();
final ExpressionType expressionType = SQL_TO_LINQ_OPERATOR_MAP.get(operator);
if (expressionType != null) {
switch (operator.getSyntax()) {
case Binary:
return Expressions.makeBinary(
expressionType, translate(call.getOperands()[0]), translate(call.getOperands()[1]));
case Postfix:
case Prefix:
return Expressions.makeUnary(expressionType, translate(call.getOperands()[0]));
default:
throw new RuntimeException("unknown syntax " + operator.getSyntax());
}
}
Method method = SQL_OP_TO_JAVA_METHOD_MAP.get(operator);
if (method != null) {
List<Expression> exprs = translateList(Arrays.asList(call.operands));
return !Modifier.isStatic(method.getModifiers())
? Expressions.call(exprs.get(0), method, exprs.subList(1, exprs.size()))
: Expressions.call(method, exprs);
}
switch (expr.getKind()) {
default:
throw new RuntimeException("cannot translate expression " + expr);
}
}
throw new RuntimeException("cannot translate expression " + expr);
}
// implement RelOptRule
public void onMatch(RelOptRuleCall call) {
CalcRel calc = call.rel(0);
RexProgram program = calc.getProgram();
if (!program.isTrivial()) {
return;
}
RelNode child = calc.getInput(0);
child = call.getPlanner().register(child, calc);
call.transformTo(convert(child, calc.getTraitSet()));
}
/**
* Burrows into a synthetic record and returns the underlying relation which provides the field
* called <code>fieldName</code>.
*/
public JavaRel implementFieldAccess(JavaRelImplementor implementor, String fieldName) {
if (!isBoxed()) {
return implementor.implementFieldAccess((JavaRel) getChild(), fieldName);
}
RelDataType type = getRowType();
int field = type.getFieldOrdinal(fieldName);
RexLocalRef ref = program.getProjectList().get(field);
final int index = ref.getIndex();
return implementor.findRel((JavaRel) this, program.getExprList().get(index));
}
// implement RelOptRule
public void onMatch(RelOptRuleCall call) {
CalcRel calcRel = (CalcRel) call.rels[0];
RexProgram program = calcRel.getProgram();
// check the projection
List<Integer> projOrdinals = new ArrayList<Integer>();
RelDataType outputRowType = isProjectSimple(calcRel, projOrdinals);
if (outputRowType == null) {
return;
}
RexLocalRef condition = program.getCondition();
CompOperatorEnum compOp = CompOperatorEnum.COMP_NOOP;
Integer[] filterOrdinals = {};
List<RexLiteral> filterLiterals = new ArrayList<RexLiteral>();
// check the condition
if (condition != null) {
RexNode filterExprs = program.expandLocalRef(condition);
List<Integer> filterList = new ArrayList<Integer>();
List<CompOperatorEnum> op = new ArrayList<CompOperatorEnum>();
if (!isConditionSimple(calcRel, filterExprs, filterList, filterLiterals, op)) {
return;
}
compOp = op.get(0);
filterOrdinals = filterList.toArray(new Integer[filterList.size()]);
}
RelNode fennelInput =
mergeTraitsAndConvert(
calcRel.getTraits(), FennelRel.FENNEL_EXEC_CONVENTION, calcRel.getChild());
if (fennelInput == null) {
return;
}
Integer[] projection = projOrdinals.toArray(new Integer[projOrdinals.size()]);
FennelReshapeRel reshapeRel =
new FennelReshapeRel(
calcRel.getCluster(),
fennelInput,
projection,
outputRowType,
compOp,
filterOrdinals,
filterLiterals,
new FennelRelParamId[] {},
new Integer[] {},
null);
call.transformTo(reshapeRel);
}
/**
* Creates a relational expression which permutes the output fields of a relational expression
* according to a permutation.
*
* <p>Optimizations:
*
* <ul>
* <li>If the relational expression is a {@link CalcRel} or {@link ProjectRel} which is already
* acting as a permutation, combines the new permutation with the old;
* <li>If the permutation is the identity, returns the original relational expression.
* </ul>
*
* <p>If a permutation is combined with its inverse, these optimizations would combine to remove
* them both.
*
* @param rel Relational expression
* @param permutation Permutation to apply to fields
* @param fieldNames Field names; if null, or if a particular entry is null, the name of the
* permuted field is used
* @return relational expression which permutes its input fields
*/
public static RelNode permute(RelNode rel, Permutation permutation, List<String> fieldNames) {
if (permutation.isIdentity()) {
return rel;
}
if (rel instanceof CalcRel) {
CalcRel calcRel = (CalcRel) rel;
Permutation permutation1 = calcRel.getProgram().getPermutation();
if (permutation1 != null) {
Permutation permutation2 = permutation.product(permutation1);
return permute(rel, permutation2, null);
}
}
if (rel instanceof ProjectRel) {
Permutation permutation1 = ((ProjectRel) rel).getPermutation();
if (permutation1 != null) {
Permutation permutation2 = permutation.product(permutation1);
return permute(rel, permutation2, null);
}
}
final List<RelDataType> outputTypeList = new ArrayList<RelDataType>();
final List<String> outputNameList = new ArrayList<String>();
final List<RexNode> exprList = new ArrayList<RexNode>();
final List<RexLocalRef> projectRefList = new ArrayList<RexLocalRef>();
final List<RelDataTypeField> fields = rel.getRowType().getFieldList();
for (int i = 0; i < permutation.getTargetCount(); i++) {
int target = permutation.getTarget(i);
final RelDataTypeField targetField = fields.get(target);
outputTypeList.add(targetField.getType());
outputNameList.add(
((fieldNames == null) || (fieldNames.size() <= i) || (fieldNames.get(i) == null))
? targetField.getName()
: fieldNames.get(i));
exprList.add(rel.getCluster().getRexBuilder().makeInputRef(fields.get(i).getType(), i));
final int source = permutation.getSource(i);
projectRefList.add(new RexLocalRef(source, fields.get(source).getType()));
}
final RexProgram program =
new RexProgram(
rel.getRowType(),
exprList,
projectRefList,
null,
rel.getCluster().getTypeFactory().createStructType(outputTypeList, outputNameList));
return new CalcRel(
rel.getCluster(),
rel.getTraitSet(),
rel,
program.getOutputRowType(),
program,
Collections.<RelCollation>emptyList());
}
/**
* Translates a {@link RexProgram} to a sequence of expressions and declarations.
*
* @param inputs Variables holding the current record of each input relational expression
* @param program Program to be translated
* @return Sequence of expressions, optional condition
*/
public static List<Expression> translateProjects(
List<Expression> inputs,
RexProgram program,
JavaTypeFactory typeFactory,
List<Statement> list) {
return new RexToLixTranslator(program, typeFactory, inputs)
.translate(list, program.getProjectList());
}
public IterCalcRel(
RelOptCluster cluster, RelNode child, RexProgram program, int flags, String tag) {
super(cluster, new RelTraitSet(CallingConvention.ITERATOR), child);
this.flags = flags;
this.program = program;
this.rowType = program.getOutputRowType();
this.tag = tag;
}
/**
* Determines if a projection is simple.
*
* @param calcRel CalcRel containing the projection
* @param projOrdinals if the projection is simple, returns the ordinals of the projection inputs
* @return rowtype corresponding to the projection, provided it is simple; otherwise null is
* returned
*/
private RelDataType isProjectSimple(CalcRel calcRel, List<Integer> projOrdinals) {
// Loop through projection expressions. If we find a non-simple
// projection expression, simply return.
RexProgram program = calcRel.getProgram();
List<RexLocalRef> projList = program.getProjectList();
int nProjExprs = projList.size();
RelDataType[] types = new RelDataType[nProjExprs];
String[] fieldNames = new String[nProjExprs];
RelDataTypeField[] projFields = calcRel.getRowType().getFields();
for (int i = 0; i < nProjExprs; i++) {
RexNode projExpr = program.expandLocalRef(projList.get(i));
if (projExpr instanceof RexInputRef) {
projOrdinals.add(((RexInputRef) projExpr).getIndex());
types[i] = projExpr.getType();
fieldNames[i] = projFields[i].getName();
continue;
} else if (!(projExpr instanceof RexCall)) {
return null;
}
RexCall rexCall = (RexCall) projExpr;
if (rexCall.getOperator() != SqlStdOperatorTable.castFunc) {
return null;
}
RexNode castOperand = rexCall.getOperands()[0];
if (!(castOperand instanceof RexInputRef)) {
return null;
}
RelDataType castType = projExpr.getType();
RelDataType origType = castOperand.getType();
if (isCastSimple(origType, castType)) {
projOrdinals.add(((RexInputRef) castOperand).getIndex());
types[i] = castType;
fieldNames[i] = projFields[i].getName();
} else {
return null;
}
}
// return the rowtype corresponding to the output of the projection
return calcRel.getCluster().getTypeFactory().createStructType(types, fieldNames);
}
/**
* Creates a relational expression which filters according to a given condition, returning the
* same fields as its input.
*
* @param child Child relational expression
* @param condition Condition
* @return Relational expression
*/
public static RelNode createFilter(RelNode child, RexNode condition) {
if (DeprecateProjectAndFilter) {
final RelOptCluster cluster = child.getCluster();
RexProgramBuilder builder =
new RexProgramBuilder(child.getRowType(), cluster.getRexBuilder());
builder.addIdentity();
builder.addCondition(condition);
final RexProgram program = builder.getProgram();
return new CalcRel(
cluster,
child.getTraitSet(),
child,
program.getOutputRowType(),
program,
Collections.<RelCollation>emptyList());
} else {
return new FilterRel(child.getCluster(), child, condition);
}
}
/**
* Determines whether it is possible to implement a set of expressions in Java.
*
* @param program Program to translate
* @return whether all expressions in the program can be implemented
*/
public boolean canTranslate(RelNode rel, RexProgram program) {
RexToOJTranslator translator = newTranslator(rel);
TranslationTester tester = new TranslationTester(translator, true);
final List<RexNode> exprList = program.getExprList();
for (RexNode expr : exprList) {
if (!tester.canTranslate(expr)) {
return false;
}
}
return true;
}
public static Expression translateCondition(
List<Expression> inputs,
RexProgram program,
JavaTypeFactory typeFactory,
List<Statement> list) {
List<Expression> x =
new RexToLixTranslator(program, typeFactory, inputs)
.translate(list, Collections.singletonList(program.getCondition()));
assert x.size() == 1;
return x.get(0);
}
/**
* Creates a relational expression which projects the output fields of a relational expression
* according to a partial mapping.
*
* <p>A partial mapping is weaker than a permutation: every target has one source, but a source
* may have 0, 1 or more than one targets. Usually the result will have fewer fields than the
* source, unless some source fields are projected multiple times.
*
* <p>This method could optimize the result as {@link #permute} does, but does not at present.
*
* @param rel Relational expression
* @param mapping Mapping from source fields to target fields. The mapping type must obey the
* constaints {@link MappingType#isMandatorySource()} and {@link
* MappingType#isSingleSource()}, as does {@link MappingType#InverseFunction}.
* @param fieldNames Field names; if null, or if a particular entry is null, the name of the
* permuted field is used
* @return relational expression which projects a subset of the input fields
*/
public static RelNode projectMapping(RelNode rel, Mapping mapping, List<String> fieldNames) {
assert mapping.getMappingType().isSingleSource();
assert mapping.getMappingType().isMandatorySource();
if (mapping.isIdentity()) {
return rel;
}
final List<RelDataType> outputTypeList = new ArrayList<RelDataType>();
final List<String> outputNameList = new ArrayList<String>();
final List<RexNode> exprList = new ArrayList<RexNode>();
final List<RexLocalRef> projectRefList = new ArrayList<RexLocalRef>();
final List<RelDataTypeField> fields = rel.getRowType().getFieldList();
for (int i = 0; i < fields.size(); i++) {
final RelDataTypeField field = fields.get(i);
exprList.add(rel.getCluster().getRexBuilder().makeInputRef(field.getType(), i));
}
for (int i = 0; i < mapping.getTargetCount(); i++) {
int source = mapping.getSource(i);
final RelDataTypeField sourceField = fields.get(source);
outputTypeList.add(sourceField.getType());
outputNameList.add(
((fieldNames == null) || (fieldNames.size() <= i) || (fieldNames.get(i) == null))
? sourceField.getName()
: fieldNames.get(i));
projectRefList.add(new RexLocalRef(source, sourceField.getType()));
}
final RexProgram program =
new RexProgram(
rel.getRowType(),
exprList,
projectRefList,
null,
rel.getCluster().getTypeFactory().createStructType(outputTypeList, outputNameList));
return new CalcRel(
rel.getCluster(),
rel.getTraitSet(),
rel,
program.getOutputRowType(),
program,
Collections.<RelCollation>emptyList());
}
public void onMatch(RelOptRuleCall call) {
CalcRel calc = (CalcRel) call.getRels()[0];
RexProgram program = calc.getProgram();
final List<RexNode> exprList = program.getExprList();
// Form a list of expressions with sub-expressions fully
// expanded.
final List<RexNode> expandedExprList = new ArrayList<RexNode>(exprList.size());
final RexShuttle shuttle =
new RexShuttle() {
public RexNode visitLocalRef(RexLocalRef localRef) {
return expandedExprList.get(localRef.getIndex());
}
};
for (RexNode expr : exprList) {
expandedExprList.add(expr.accept(shuttle));
}
if (reduceExpressions(calc, expandedExprList)) {
final RexProgramBuilder builder =
new RexProgramBuilder(
calc.getChild().getRowType(), calc.getCluster().getRexBuilder());
List<RexLocalRef> list = new ArrayList<RexLocalRef>();
for (RexNode expr : expandedExprList) {
list.add(builder.registerInput(expr));
}
if (program.getCondition() != null) {
final int conditionIndex = program.getCondition().getIndex();
final RexNode newConditionExp = expandedExprList.get(conditionIndex);
if (newConditionExp.isAlwaysTrue()) {
// condition is always TRUE - drop it
} else if ((newConditionExp instanceof RexLiteral)
|| RexUtil.isNullLiteral(newConditionExp, true)) {
// condition is always NULL or FALSE - replace calc
// with empty
call.transformTo(new EmptyRel(calc.getCluster(), calc.getRowType()));
return;
} else {
builder.addCondition(list.get(conditionIndex));
}
}
int k = 0;
for (RexLocalRef projectExpr : program.getProjectList()) {
final int index = projectExpr.getIndex();
builder.addProject(
list.get(index).getIndex(),
program.getOutputRowType().getFieldList().get(k++).getName());
}
call.transformTo(
new CalcRel(
calc.getCluster(),
calc.getTraits(),
calc.getChild(),
calc.getRowType(),
builder.getProgram(),
calc.getCollationList()));
// New plan is absolutely better than old plan.
call.getPlanner().setImportance(calc, 0.0);
}
}
/** 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);
}
}
@Override
public CalcRelBase copy(
RelTraitSet traitSet, RelNode child, RexProgram program, List<RelCollation> collationList) {
return new CalcRel(
getCluster(), traitSet, child, program.getOutputRowType(), program, collationList);
}
public RelOptCost computeSelfCost(RelOptPlanner planner) {
double dRows = RelMetadataQuery.getRowCount(this);
double dCpu = RelMetadataQuery.getRowCount(getChild()) * program.getExprCount();
double dIo = 0;
return planner.makeCost(dRows, dCpu, dIo);
}
public IterCalcRel clone() {
IterCalcRel clone =
new IterCalcRel(getCluster(), getChild().clone(), program.copy(), getFlags(), tag);
clone.inheritTraitsFrom(this);
return clone;
}
/**
* Generates code for a Java expression satisfying the {@link org.eigenbase.runtime.TupleIter}
* interface. The generated code allocates a {@link org.eigenbase.runtime.CalcTupleIter} with a
* dynamic {@link org.eigenbase.runtime.TupleIter#fetchNext()} method. If the "abort on error"
* flag is false, or an error handling tag is specified, then fetchNext is written to handle row
* errors.
*
* <p>Row errors are handled by wrapping expressions that can fail with a try/catch block. A
* caught RuntimeException is then published to an "connection variable." In the event that errors
* can overflow, an "error buffering" flag allows them to be posted again on the next iteration of
* fetchNext.
*
* @param implementor an object that implements relations as Java code
* @param rel the relation to be implemented
* @param childExp the implemented child of the relation
* @param varInputRow the Java variable to use for the input row
* @param inputRowType the rel data type of the input row
* @param outputRowType the rel data type of the output row
* @param program the rex program to implemented by the relation
* @param tag an error handling tag
* @return a Java expression satisfying the TupleIter interface
*/
public static Expression implementAbstractTupleIter(
JavaRelImplementor implementor,
JavaRel rel,
Expression childExp,
Variable varInputRow,
final RelDataType inputRowType,
final RelDataType outputRowType,
RexProgram program,
String tag) {
MemberDeclarationList memberList = new MemberDeclarationList();
// Perform error recovery if continuing on errors or if
// an error handling tag has been specified
boolean errorRecovery = !abortOnError || (tag != null);
// Error buffering should not be enabled unless error recovery is
assert !errorBuffering || errorRecovery;
// Allow backwards compatibility until all Farrago extensions are
// satisfied with the new error handling semantics. The new semantics
// include:
// (1) cast input object to input row object outside of try block,
// should be fine, at least for base Farrago
// (2) maintain a columnIndex counter to better locate of error,
// at the cost of a few cycles
// (3) publish errors to the runtime context. FarragoRuntimeContext
// now supports this API
boolean backwardsCompatible = true;
if (tag != null) {
backwardsCompatible = false;
}
RelDataTypeFactory typeFactory = implementor.getTypeFactory();
OJClass outputRowClass = OJUtil.typeToOJClass(outputRowType, typeFactory);
OJClass inputRowClass = OJUtil.typeToOJClass(inputRowType, typeFactory);
Variable varOutputRow = implementor.newVariable();
FieldDeclaration inputRowVarDecl =
new FieldDeclaration(
new ModifierList(ModifierList.PRIVATE),
TypeName.forOJClass(inputRowClass),
varInputRow.toString(),
null);
FieldDeclaration outputRowVarDecl =
new FieldDeclaration(
new ModifierList(ModifierList.PRIVATE),
TypeName.forOJClass(outputRowClass),
varOutputRow.toString(),
new AllocationExpression(outputRowClass, new ExpressionList()));
// The method body for fetchNext, a main target of code generation
StatementList nextMethodBody = new StatementList();
// First, post an error if it overflowed the previous time
// if (pendingError) {
// rc = handleRowError(...);
// if (rc instanceof NoDataReason) {
// return rc;
// }
// pendingError = false;
// }
if (errorBuffering) {
// add to next method body...
}
// Most of fetchNext falls within a while() block. The while block
// allows us to try multiple input rows against a filter condition
// before returning a single row.
// while (true) {
// Object varInputObj = inputIterator.fetchNext();
// if (varInputObj instanceof TupleIter.NoDataReason) {
// return varInputObj;
// }
// varInputRow = (InputRowClass) varInputObj;
// int columnIndex = 0;
// [calculation statements]
// }
StatementList whileBody = new StatementList();
Variable varInputObj = implementor.newVariable();
whileBody.add(
new VariableDeclaration(
OJUtil.typeNameForClass(Object.class),
varInputObj.toString(),
new MethodCall(new FieldAccess("inputIterator"), "fetchNext", new ExpressionList())));
StatementList ifNoDataReasonBody = new StatementList();
whileBody.add(
new IfStatement(
new InstanceofExpression(
varInputObj, OJUtil.typeNameForClass(TupleIter.NoDataReason.class)),
ifNoDataReasonBody));
ifNoDataReasonBody.add(new ReturnStatement(varInputObj));
// Push up the row declaration for new error handling so that the
// input row is available to the error handler
if (!backwardsCompatible) {
whileBody.add(assignInputRow(inputRowClass, varInputRow, varInputObj));
}
Variable varColumnIndex = null;
if (errorRecovery && !backwardsCompatible) {
// NOTE jvs 7-Oct-2006: Declare varColumnIndex as a member
// (rather than a local) in case in the future we want
// to decompose complex expressions into helper methods.
varColumnIndex = implementor.newVariable();
FieldDeclaration varColumnIndexDecl =
new FieldDeclaration(
new ModifierList(ModifierList.PRIVATE),
OJUtil.typeNameForClass(int.class),
varColumnIndex.toString(),
null);
memberList.add(varColumnIndexDecl);
whileBody.add(
new ExpressionStatement(
new AssignmentExpression(
varColumnIndex, AssignmentExpression.EQUALS, Literal.makeLiteral(0))));
}
// Calculator (projection, filtering) statements are later appended
// to calcStmts. Typically, this target will be the while list itself.
StatementList calcStmts;
if (!errorRecovery) {
calcStmts = whileBody;
} else {
// For error recovery, we wrap the calc statements
// (e.g., everything but the code that reads rows from the
// inputIterator) in a try/catch that publishes exceptions.
calcStmts = new StatementList();
// try { /* calcStmts */ }
// catch(RuntimeException ex) {
// Object rc = connection.handleRowError(...);
// [buffer error if necessary]
// }
StatementList catchStmts = new StatementList();
if (backwardsCompatible) {
catchStmts.add(
new ExpressionStatement(
new MethodCall(
new MethodCall(
OJUtil.typeNameForClass(EigenbaseTrace.class), "getStatementTracer", null),
"log",
new ExpressionList(
new FieldAccess(OJUtil.typeNameForClass(Level.class), "WARNING"),
Literal.makeLiteral("java calc exception"),
new FieldAccess("ex")))));
} else {
Variable varRc = implementor.newVariable();
ExpressionList handleRowErrorArgs =
new ExpressionList(varInputRow, new FieldAccess("ex"), varColumnIndex);
handleRowErrorArgs.add(Literal.makeLiteral(tag));
catchStmts.add(
new VariableDeclaration(
OJUtil.typeNameForClass(Object.class),
varRc.toString(),
new MethodCall(
implementor.getConnectionVariable(), "handleRowError", handleRowErrorArgs)));
// Buffer an error if it overflowed
// if (rc instanceof NoDataReason) {
// pendingError = true;
// [save error state]
// return rc;
// }
if (errorBuffering) {
// add to catch statements...
}
}
CatchList catchList =
new CatchList(
new CatchBlock(
new Parameter(OJUtil.typeNameForClass(RuntimeException.class), "ex"),
catchStmts));
TryStatement tryStmt = new TryStatement(calcStmts, catchList);
whileBody.add(tryStmt);
}
if (backwardsCompatible) {
calcStmts.add(assignInputRow(inputRowClass, varInputRow, varInputObj));
}
StatementList condBody;
RexToOJTranslator translator = implementor.newStmtTranslator(rel, calcStmts, memberList);
try {
translator.pushProgram(program);
if (program.getCondition() != null) {
// TODO jvs 8-Oct-2006: move condition to its own
// method if big, as below for project exprs.
condBody = new StatementList();
RexNode rexIsTrue =
rel.getCluster()
.getRexBuilder()
.makeCall(SqlStdOperatorTable.isTrueOperator, program.getCondition());
Expression conditionExp = translator.translateRexNode(rexIsTrue);
calcStmts.add(new IfStatement(conditionExp, condBody));
} else {
condBody = calcStmts;
}
RelDataTypeField[] fields = outputRowType.getFields();
final List<RexLocalRef> projectRefList = program.getProjectList();
int i = -1;
for (RexLocalRef rhs : projectRefList) {
// NOTE jvs 14-Sept-2006: Put complicated project expressions
// into their own method, otherwise a big select list can easily
// blow the 64K Java limit on method bytecode size. Make
// methods private final in the hopes that they will get inlined
// JIT. For now we decide "complicated" based on the size of
// the generated Java parse tree. A big enough select list of
// simple expressions could still blow the limit, so we may need
// to group them together, sub-divide, etc.
StatementList projMethodBody = new StatementList();
if (errorRecovery && !backwardsCompatible) {
projMethodBody.add(
new ExpressionStatement(
new UnaryExpression(varColumnIndex, UnaryExpression.POST_INCREMENT)));
}
++i;
RexToOJTranslator projTranslator = translator.push(projMethodBody);
String javaFieldName = Util.toJavaId(fields[i].getName(), i);
Expression lhs = new FieldAccess(varOutputRow, javaFieldName);
projTranslator.translateAssignment(fields[i], lhs, rhs);
int complexity = OJUtil.countParseTreeNodes(projMethodBody);
// REVIEW: HCP 5/18/2011
// The projMethod should be checked
// for causing possible compiler errors caused by the use of
// variables declared in other projMethods. Also the
// local declaration of variabled used by other proj methods
// should also be checked.
// Fixing for backswing integration 14270
// TODO: check if abstracting this method body will cause
// a compiler error
if (true) {
// No method needed; just append.
condBody.addAll(projMethodBody);
continue;
}
// Need a separate method.
String projMethodName = "calc_" + varOutputRow.toString() + "_f_" + i;
MemberDeclaration projMethodDecl =
new MethodDeclaration(
new ModifierList(ModifierList.PRIVATE | ModifierList.FINAL),
TypeName.forOJClass(OJSystem.VOID),
projMethodName,
new ParameterList(),
null,
projMethodBody);
memberList.add(projMethodDecl);
condBody.add(new ExpressionStatement(new MethodCall(projMethodName, new ExpressionList())));
}
} finally {
translator.popProgram(program);
}
condBody.add(new ReturnStatement(varOutputRow));
WhileStatement whileStmt = new WhileStatement(Literal.makeLiteral(true), whileBody);
nextMethodBody.add(whileStmt);
MemberDeclaration fetchNextMethodDecl =
new MethodDeclaration(
new ModifierList(ModifierList.PUBLIC),
OJUtil.typeNameForClass(Object.class),
"fetchNext",
new ParameterList(),
null,
nextMethodBody);
// The restart() method should reset variables used to buffer errors
// pendingError = false
if (errorBuffering) {
// declare refinement of restart() and add to member list...
}
memberList.add(inputRowVarDecl);
memberList.add(outputRowVarDecl);
memberList.add(fetchNextMethodDecl);
Expression newTupleIterExp =
new AllocationExpression(
OJUtil.typeNameForClass(CalcTupleIter.class), new ExpressionList(childExp), memberList);
return newTupleIterExp;
}
public void explain(RelOptPlanWriter pw) {
program.explainCalc(this, pw);
}