Examples with ILangExpression org.apache.asterix.lang.common.base.ILangExpression used on opensource projects

Example 26 with ILangExpression

use of org.apache.asterix.lang.common.base.ILangExpression in project asterixdb by apache.

the class SubstituteGroupbyExpressionVisitor method visit.

@Override
public Expression visit(SelectBlock selectBlock, ILangExpression arg) throws CompilationException {
    if (selectBlock.hasGroupbyClause()) {
        Map<Expression, Expression> map = new HashMap<>();
        for (GbyVariableExpressionPair gbyKeyPair : selectBlock.getGroupbyClause().getGbyPairList()) {
            Expression gbyKeyExpr = gbyKeyPair.getExpr();
            if (gbyKeyExpr.getKind() != Kind.VARIABLE_EXPRESSION) {
                map.put(gbyKeyExpr, gbyKeyPair.getVar());
            }
        }
        // Creates a substitution visitor.
        SubstituteGroupbyExpressionVisitor visitor = new SubstituteGroupbyExpressionVisitor(context, map);
        // Rewrites LET/HAVING/SELECT clauses.
        if (selectBlock.hasLetClausesAfterGroupby()) {
            for (LetClause letClause : selectBlock.getLetListAfterGroupby()) {
                letClause.accept(this, arg);
            }
        }
        if (selectBlock.hasHavingClause()) {
            selectBlock.getHavingClause().accept(visitor, arg);
        }
        selectBlock.getSelectClause().accept(visitor, arg);
        SelectExpression selectExpression = (SelectExpression) arg;
        // For SET operation queries, the GROUP BY key variables will not substitute ORDER BY nor LIMIT expressions.
        if (!selectExpression.getSelectSetOperation().hasRightInputs()) {
            if (selectExpression.hasOrderby()) {
                selectExpression.getOrderbyClause().accept(visitor, arg);
            }
            if (selectExpression.hasLimit()) {
                selectExpression.getLimitClause().accept(visitor, arg);
            }
        }
    }
    return super.visit(selectBlock, arg);
}

Example 27 with ILangExpression

use of org.apache.asterix.lang.common.base.ILangExpression in project asterixdb by apache.

the class SqlppAstPrintUtil method toString.

/**
     * @param exprs
     *            a list of language expression.
     * @return an AST of the input language expressions.
     * @throws CompilationException
     */
public static String toString(List<ILangExpression> exprs) throws CompilationException {
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    PrintWriter output = new PrintWriter(bos);
    QueryPrintVisitor visitor = astPrintVisitorFactory.createLangVisitor(output);
    for (ILangExpression expr : exprs) {
        expr.accept(visitor, 0);
    }
    output.close();
    return bos.toString();
}

Example 28 with ILangExpression

use of org.apache.asterix.lang.common.base.ILangExpression in project asterixdb by apache.

the class SqlppExpressionToPlanTranslator method visit.

@Override
public Pair<ILogicalOperator, LogicalVariable> visit(SelectSetOperation selectSetOperation, Mutable<ILogicalOperator> tupSource) throws CompilationException {
    SetOperationInput leftInput = selectSetOperation.getLeftInput();
    if (!selectSetOperation.hasRightInputs()) {
        return leftInput.accept(this, tupSource);
    }
    List<ILangExpression> inputExprs = new ArrayList<>();
    inputExprs.add(leftInput.selectBlock() ? new SelectExpression(null, new SelectSetOperation(leftInput, null), null, null, true) : leftInput.getSubquery());
    for (SetOperationRight setOperationRight : selectSetOperation.getRightInputs()) {
        SetOpType setOpType = setOperationRight.getSetOpType();
        if (setOpType != SetOpType.UNION || setOperationRight.isSetSemantics()) {
            throw new CompilationException("Operation " + setOpType + (setOperationRight.isSetSemantics() ? " with set semantics" : "ALL") + " is not supported.");
        }
        SetOperationInput rightInput = setOperationRight.getSetOperationRightInput();
        inputExprs.add(rightInput.selectBlock() ? new SelectExpression(null, new SelectSetOperation(rightInput, null), null, null, true) : rightInput.getSubquery());
    }
    return translateUnionAllFromInputExprs(inputExprs, tupSource);
}

Example 29 with ILangExpression

use of org.apache.asterix.lang.common.base.ILangExpression in project asterixdb by apache.

the class CloneAndSubstituteVariablesVisitor method visit.

@Override
public Pair<ILangExpression, VariableSubstitutionEnvironment> visit(LetClause lc, VariableSubstitutionEnvironment env) throws CompilationException {
    Pair<ILangExpression, VariableSubstitutionEnvironment> p1 = lc.getBindingExpr().accept(this, env);
    VariableExpr varExpr = lc.getVarExpr();
    VariableExpr newVe = generateNewVariable(context, varExpr);
    LetClause newLet = new LetClause(newVe, (Expression) p1.first);
    return new Pair<>(newLet, VariableCloneAndSubstitutionUtil.eliminateSubstFromList(lc.getVarExpr(), env));
}

Example 30 with ILangExpression

use of org.apache.asterix.lang.common.base.ILangExpression in project asterixdb by apache.

the class CloneAndSubstituteVariablesVisitor method visit.

@Override
public Pair<ILangExpression, VariableSubstitutionEnvironment> visit(LimitClause lc, VariableSubstitutionEnvironment env) throws CompilationException {
    Pair<ILangExpression, VariableSubstitutionEnvironment> p1 = lc.getLimitExpr().accept(this, env);
    Pair<ILangExpression, VariableSubstitutionEnvironment> p2;
    Expression lcOffsetExpr = lc.getOffset();
    if (lcOffsetExpr != null) {
        p2 = lcOffsetExpr.accept(this, env);
    } else {
        p2 = new Pair<>(null, null);
    }
    LimitClause c = new LimitClause((Expression) p1.first, (Expression) p2.first);
    return new Pair<>(c, env);
}