Examples with Query org.apache.asterix.lang.common.statement.Query used on opensource projects

Example 1 with Query

use of org.apache.asterix.lang.common.statement.Query in project asterixdb by apache.

the class SqlppDeleteRewriteVisitor method visit.

@Override
public Void visit(DeleteStatement deleteStmt, Void visitArg) {
    List<Expression> arguments = new ArrayList<>();
    Identifier dataverseName = deleteStmt.getDataverseName();
    Identifier datasetName = deleteStmt.getDatasetName();
    String arg = dataverseName == null ? datasetName.getValue() : dataverseName.getValue() + "." + datasetName.getValue();
    LiteralExpr argumentLiteral = new LiteralExpr(new StringLiteral(arg));
    arguments.add(argumentLiteral);
    CallExpr callExpression = new CallExpr(new FunctionSignature(FunctionConstants.ASTERIX_NS, "dataset", 1), arguments);
    // From clause.
    VariableExpr var = deleteStmt.getVariableExpr();
    FromTerm fromTerm = new FromTerm(callExpression, var, null, null);
    @SuppressWarnings("unchecked") FromClause fromClause = new FromClause(Collections.singletonList(fromTerm));
    // Where clause.
    WhereClause whereClause = null;
    Expression condition = deleteStmt.getCondition();
    if (condition != null) {
        whereClause = new WhereClause(condition);
    }
    // Select clause.
    VariableExpr returnExpr = new VariableExpr(var.getVar());
    returnExpr.setIsNewVar(false);
    SelectElement selectElement = new SelectElement(returnExpr);
    SelectClause selectClause = new SelectClause(selectElement, null, false);
    // Construct the select expression.
    SelectBlock selectBlock = new SelectBlock(selectClause, fromClause, null, whereClause, null, null, null);
    SelectSetOperation selectSetOperation = new SelectSetOperation(new SetOperationInput(selectBlock, null), null);
    SelectExpression selectExpression = new SelectExpression(null, selectSetOperation, null, null, false);
    Query query = new Query(false, false, selectExpression, 0);
    query.setBody(selectExpression);
    // return the delete statement.
    deleteStmt.setQuery(query);
    return null;
}

Example 2 with Query

use of org.apache.asterix.lang.common.statement.Query in project asterixdb by apache.

the class SqlppRewriteUtil method substituteExpression.

/**
     * Substitutes expression with replacement expressions according to the exprMap.
     *
     * @param expression
     *            ,
     *            an input expression.
     * @param exprMap
     *            a map that maps expressions to their corresponding replacement expressions.
     * @return an expression, where sub-expressions of the input expression (including the input expression itself)
     *         are replaced with deep copies with their mapped replacements in the exprMap if there exists such a
     *         replacement expression.
     * @throws CompilationException
     */
public static Expression substituteExpression(Expression expression, Map<Expression, Expression> exprMap, LangRewritingContext context) throws CompilationException {
    if (exprMap.isEmpty()) {
        return expression;
    }
    // Creates a wrapper query for the expression so that if the expression itself
    // is the key, it can also be replaced.
    Query wrapper = new Query(false);
    wrapper.setBody(expression);
    // Creates a substitution visitor.
    SqlppSubstituteExpressionVisitor visitor = new SqlppSubstituteExpressionVisitor(context, exprMap);
    wrapper.accept(visitor, wrapper);
    return wrapper.getBody();
}

Example 3 with Query

use of org.apache.asterix.lang.common.statement.Query in project asterixdb by apache.

the class AbstractInlineUdfsVisitor method rewriteFunctionBody.

protected Expression rewriteFunctionBody(Expression expr) throws CompilationException {
    Query wrappedQuery = new Query(false);
    wrappedQuery.setBody(expr);
    wrappedQuery.setTopLevel(false);
    IQueryRewriter queryRewriter = rewriterFactory.createQueryRewriter();
    queryRewriter.rewrite(declaredFunctions, wrappedQuery, metadataProvider, context);
    return wrappedQuery.getBody();
}

Example 4 with Query

use of org.apache.asterix.lang.common.statement.Query in project asterixdb by apache.

the class CloneAndSubstituteVariablesVisitor method visit.

@Override
public Pair<ILangExpression, VariableSubstitutionEnvironment> visit(Query q, VariableSubstitutionEnvironment env) throws CompilationException {
    Query newQ = new Query(q.isExplain());
    Pair<ILangExpression, VariableSubstitutionEnvironment> p1 = q.getBody().accept(this, env);
    newQ.setBody((Expression) p1.first);
    return new Pair<>(newQ, p1.second);
}

Example 5 with Query

use of org.apache.asterix.lang.common.statement.Query in project asterixdb by apache.

the class AqlDeleteRewriteVisitor method visit.

@Override
public Void visit(DeleteStatement deleteStmt, Void visitArg) {
    List<Expression> arguments = new ArrayList<>();
    Identifier dataverseName = deleteStmt.getDataverseName();
    Identifier datasetName = deleteStmt.getDatasetName();
    String arg = dataverseName == null ? datasetName.getValue() : dataverseName.getValue() + "." + datasetName.getValue();
    LiteralExpr argumentLiteral = new LiteralExpr(new StringLiteral(arg));
    arguments.add(argumentLiteral);
    CallExpr callExpression = new CallExpr(new FunctionSignature(FunctionConstants.ASTERIX_NS, "dataset", 1), arguments);
    List<Clause> clauseList = new ArrayList<>();
    VariableExpr var = deleteStmt.getVariableExpr();
    Clause forClause = new ForClause(var, callExpression);
    clauseList.add(forClause);
    Clause whereClause = null;
    Expression condition = deleteStmt.getCondition();
    if (condition != null) {
        whereClause = new WhereClause(condition);
        clauseList.add(whereClause);
    }
    VariableExpr returnExpr = new VariableExpr(var.getVar());
    returnExpr.setIsNewVar(false);
    FLWOGRExpression flowgr = new FLWOGRExpression(clauseList, returnExpr);
    Query query = new Query(false);
    query.setBody(flowgr);
    deleteStmt.setQuery(query);
    return null;
}