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Example 1 with SqlWith

use of org.apache.calcite.sql.SqlWith in project calcite by apache.

the class SqlValidatorImpl method performUnconditionalRewrites.

/**
 * Performs expression rewrites which are always used unconditionally. These
 * rewrites massage the expression tree into a standard form so that the
 * rest of the validation logic can be simpler.
 *
 * @param node      expression to be rewritten
 * @param underFrom whether node appears directly under a FROM clause
 * @return rewritten expression
 */
protected SqlNode performUnconditionalRewrites(SqlNode node, boolean underFrom) {
    if (node == null) {
        return node;
    }
    SqlNode newOperand;
    // first transform operands and invoke generic call rewrite
    if (node instanceof SqlCall) {
        if (node instanceof SqlMerge) {
            validatingSqlMerge = true;
        }
        SqlCall call = (SqlCall) node;
        final SqlKind kind = call.getKind();
        final List<SqlNode> operands = call.getOperandList();
        for (int i = 0; i < operands.size(); i++) {
            SqlNode operand = operands.get(i);
            boolean childUnderFrom;
            if (kind == SqlKind.SELECT) {
                childUnderFrom = i == SqlSelect.FROM_OPERAND;
            } else if (kind == SqlKind.AS && (i == 0)) {
                // for an aliased expression, it is under FROM if
                // the AS expression is under FROM
                childUnderFrom = underFrom;
            } else {
                childUnderFrom = false;
            }
            newOperand = performUnconditionalRewrites(operand, childUnderFrom);
            if (newOperand != null && newOperand != operand) {
                call.setOperand(i, newOperand);
            }
        }
        if (call.getOperator() instanceof SqlUnresolvedFunction) {
            assert call instanceof SqlBasicCall;
            final SqlUnresolvedFunction function = (SqlUnresolvedFunction) call.getOperator();
            // This function hasn't been resolved yet.  Perform
            // a half-hearted resolution now in case it's a
            // builtin function requiring special casing.  If it's
            // not, we'll handle it later during overload resolution.
            final List<SqlOperator> overloads = new ArrayList<>();
            opTab.lookupOperatorOverloads(function.getNameAsId(), function.getFunctionType(), SqlSyntax.FUNCTION, overloads);
            if (overloads.size() == 1) {
                ((SqlBasicCall) call).setOperator(overloads.get(0));
            }
        }
        if (rewriteCalls) {
            node = call.getOperator().rewriteCall(this, call);
        }
    } else if (node instanceof SqlNodeList) {
        SqlNodeList list = (SqlNodeList) node;
        for (int i = 0, count = list.size(); i < count; i++) {
            SqlNode operand = list.get(i);
            newOperand = performUnconditionalRewrites(operand, false);
            if (newOperand != null) {
                list.getList().set(i, newOperand);
            }
        }
    }
    // now transform node itself
    final SqlKind kind = node.getKind();
    switch(kind) {
        case VALUES:
            // CHECKSTYLE: IGNORE 1
            if (underFrom || true) {
                // over and over
                return node;
            } else {
                final SqlNodeList selectList = new SqlNodeList(SqlParserPos.ZERO);
                selectList.add(SqlIdentifier.star(SqlParserPos.ZERO));
                return new SqlSelect(node.getParserPosition(), null, selectList, node, null, null, null, null, null, null, null);
            }
        case ORDER_BY:
            {
                SqlOrderBy orderBy = (SqlOrderBy) node;
                handleOffsetFetch(orderBy.offset, orderBy.fetch);
                if (orderBy.query instanceof SqlSelect) {
                    SqlSelect select = (SqlSelect) orderBy.query;
                    // an order-sensitive function like RANK.
                    if (select.getOrderList() == null) {
                        // push ORDER BY into existing select
                        select.setOrderBy(orderBy.orderList);
                        select.setOffset(orderBy.offset);
                        select.setFetch(orderBy.fetch);
                        return select;
                    }
                }
                if (orderBy.query instanceof SqlWith && ((SqlWith) orderBy.query).body instanceof SqlSelect) {
                    SqlWith with = (SqlWith) orderBy.query;
                    SqlSelect select = (SqlSelect) with.body;
                    // an order-sensitive function like RANK.
                    if (select.getOrderList() == null) {
                        // push ORDER BY into existing select
                        select.setOrderBy(orderBy.orderList);
                        select.setOffset(orderBy.offset);
                        select.setFetch(orderBy.fetch);
                        return with;
                    }
                }
                final SqlNodeList selectList = new SqlNodeList(SqlParserPos.ZERO);
                selectList.add(SqlIdentifier.star(SqlParserPos.ZERO));
                final SqlNodeList orderList;
                if (getInnerSelect(node) != null && isAggregate(getInnerSelect(node))) {
                    orderList = SqlNode.clone(orderBy.orderList);
                    // We assume that ORDER BY item is present in SELECT list.
                    for (int i = 0; i < orderList.size(); i++) {
                        SqlNode sqlNode = orderList.get(i);
                        SqlNodeList selectList2 = getInnerSelect(node).getSelectList();
                        for (Ord<SqlNode> sel : Ord.zip(selectList2)) {
                            if (stripAs(sel.e).equalsDeep(sqlNode, Litmus.IGNORE)) {
                                orderList.set(i, SqlLiteral.createExactNumeric(Integer.toString(sel.i + 1), SqlParserPos.ZERO));
                            }
                        }
                    }
                } else {
                    orderList = orderBy.orderList;
                }
                return new SqlSelect(SqlParserPos.ZERO, null, selectList, orderBy.query, null, null, null, null, orderList, orderBy.offset, orderBy.fetch);
            }
        case EXPLICIT_TABLE:
            {
                // (TABLE t) is equivalent to (SELECT * FROM t)
                SqlCall call = (SqlCall) node;
                final SqlNodeList selectList = new SqlNodeList(SqlParserPos.ZERO);
                selectList.add(SqlIdentifier.star(SqlParserPos.ZERO));
                return new SqlSelect(SqlParserPos.ZERO, null, selectList, call.operand(0), null, null, null, null, null, null, null);
            }
        case DELETE:
            {
                SqlDelete call = (SqlDelete) node;
                SqlSelect select = createSourceSelectForDelete(call);
                call.setSourceSelect(select);
                break;
            }
        case UPDATE:
            {
                SqlUpdate call = (SqlUpdate) node;
                SqlSelect select = createSourceSelectForUpdate(call);
                call.setSourceSelect(select);
                // in which case leave it alone).
                if (!validatingSqlMerge) {
                    SqlNode selfJoinSrcExpr = getSelfJoinExprForUpdate(call.getTargetTable(), UPDATE_SRC_ALIAS);
                    if (selfJoinSrcExpr != null) {
                        node = rewriteUpdateToMerge(call, selfJoinSrcExpr);
                    }
                }
                break;
            }
        case MERGE:
            {
                SqlMerge call = (SqlMerge) node;
                rewriteMerge(call);
                break;
            }
    }
    return node;
}
Also used : Ord(org.apache.calcite.linq4j.Ord) SqlCall(org.apache.calcite.sql.SqlCall) SqlOperator(org.apache.calcite.sql.SqlOperator) SqlWith(org.apache.calcite.sql.SqlWith) ArrayList(java.util.ArrayList) SqlKind(org.apache.calcite.sql.SqlKind) SqlUpdate(org.apache.calcite.sql.SqlUpdate) SqlMerge(org.apache.calcite.sql.SqlMerge) SqlSelect(org.apache.calcite.sql.SqlSelect) SqlBasicCall(org.apache.calcite.sql.SqlBasicCall) SqlDelete(org.apache.calcite.sql.SqlDelete) SqlNodeList(org.apache.calcite.sql.SqlNodeList) SqlOrderBy(org.apache.calcite.sql.SqlOrderBy) SqlNode(org.apache.calcite.sql.SqlNode) SqlUnresolvedFunction(org.apache.calcite.sql.SqlUnresolvedFunction)

Example 2 with SqlWith

use of org.apache.calcite.sql.SqlWith in project flink by apache.

the class SqlValidatorImpl method performUnconditionalRewrites.

/**
 * Performs expression rewrites which are always used unconditionally. These rewrites massage
 * the expression tree into a standard form so that the rest of the validation logic can be
 * simpler.
 *
 * @param node expression to be rewritten
 * @param underFrom whether node appears directly under a FROM clause
 * @return rewritten expression
 */
protected SqlNode performUnconditionalRewrites(SqlNode node, boolean underFrom) {
    if (node == null) {
        return null;
    }
    SqlNode newOperand;
    // first transform operands and invoke generic call rewrite
    if (node instanceof SqlCall) {
        if (node instanceof SqlMerge) {
            validatingSqlMerge = true;
        }
        SqlCall call = (SqlCall) node;
        final SqlKind kind = call.getKind();
        final List<SqlNode> operands = call.getOperandList();
        for (int i = 0; i < operands.size(); i++) {
            SqlNode operand = operands.get(i);
            boolean childUnderFrom;
            if (kind == SqlKind.SELECT) {
                childUnderFrom = i == SqlSelect.FROM_OPERAND;
            } else if (kind == SqlKind.AS && (i == 0)) {
                // for an aliased expression, it is under FROM if
                // the AS expression is under FROM
                childUnderFrom = underFrom;
            } else {
                childUnderFrom = false;
            }
            newOperand = performUnconditionalRewrites(operand, childUnderFrom);
            if (newOperand != null && newOperand != operand) {
                call.setOperand(i, newOperand);
            }
        }
        if (call.getOperator() instanceof SqlUnresolvedFunction) {
            assert call instanceof SqlBasicCall;
            final SqlUnresolvedFunction function = (SqlUnresolvedFunction) call.getOperator();
            // This function hasn't been resolved yet.  Perform
            // a half-hearted resolution now in case it's a
            // builtin function requiring special casing.  If it's
            // not, we'll handle it later during overload resolution.
            final List<SqlOperator> overloads = new ArrayList<>();
            opTab.lookupOperatorOverloads(function.getNameAsId(), function.getFunctionType(), SqlSyntax.FUNCTION, overloads, catalogReader.nameMatcher());
            if (overloads.size() == 1) {
                ((SqlBasicCall) call).setOperator(overloads.get(0));
            }
        }
        if (config.callRewrite()) {
            node = call.getOperator().rewriteCall(this, call);
        }
    } else if (node instanceof SqlNodeList) {
        SqlNodeList list = (SqlNodeList) node;
        for (int i = 0, count = list.size(); i < count; i++) {
            SqlNode operand = list.get(i);
            newOperand = performUnconditionalRewrites(operand, false);
            if (newOperand != null) {
                list.getList().set(i, newOperand);
            }
        }
    }
    // now transform node itself
    final SqlKind kind = node.getKind();
    switch(kind) {
        case VALUES:
            // CHECKSTYLE: IGNORE 1
            if (underFrom || true) {
                // over and over
                return node;
            } else {
                final SqlNodeList selectList = new SqlNodeList(SqlParserPos.ZERO);
                selectList.add(SqlIdentifier.star(SqlParserPos.ZERO));
                return new SqlSelect(node.getParserPosition(), null, selectList, node, null, null, null, null, null, null, null, null);
            }
        case ORDER_BY:
            {
                SqlOrderBy orderBy = (SqlOrderBy) node;
                handleOffsetFetch(orderBy.offset, orderBy.fetch);
                if (orderBy.query instanceof SqlSelect) {
                    SqlSelect select = (SqlSelect) orderBy.query;
                    // an order-sensitive function like RANK.
                    if (select.getOrderList() == null) {
                        // push ORDER BY into existing select
                        select.setOrderBy(orderBy.orderList);
                        select.setOffset(orderBy.offset);
                        select.setFetch(orderBy.fetch);
                        return select;
                    }
                }
                if (orderBy.query instanceof SqlWith && ((SqlWith) orderBy.query).body instanceof SqlSelect) {
                    SqlWith with = (SqlWith) orderBy.query;
                    SqlSelect select = (SqlSelect) with.body;
                    // an order-sensitive function like RANK.
                    if (select.getOrderList() == null) {
                        // push ORDER BY into existing select
                        select.setOrderBy(orderBy.orderList);
                        select.setOffset(orderBy.offset);
                        select.setFetch(orderBy.fetch);
                        return with;
                    }
                }
                final SqlNodeList selectList = new SqlNodeList(SqlParserPos.ZERO);
                selectList.add(SqlIdentifier.star(SqlParserPos.ZERO));
                final SqlNodeList orderList;
                if (getInnerSelect(node) != null && isAggregate(getInnerSelect(node))) {
                    orderList = SqlNode.clone(orderBy.orderList);
                    // We assume that ORDER BY item is present in SELECT list.
                    for (int i = 0; i < orderList.size(); i++) {
                        SqlNode sqlNode = orderList.get(i);
                        SqlNodeList selectList2 = getInnerSelect(node).getSelectList();
                        for (Ord<SqlNode> sel : Ord.zip(selectList2)) {
                            if (stripAs(sel.e).equalsDeep(sqlNode, Litmus.IGNORE)) {
                                orderList.set(i, SqlLiteral.createExactNumeric(Integer.toString(sel.i + 1), SqlParserPos.ZERO));
                            }
                        }
                    }
                } else {
                    orderList = orderBy.orderList;
                }
                return new SqlSelect(SqlParserPos.ZERO, null, selectList, orderBy.query, null, null, null, null, orderList, orderBy.offset, orderBy.fetch, null);
            }
        case EXPLICIT_TABLE:
            {
                // (TABLE t) is equivalent to (SELECT * FROM t)
                SqlCall call = (SqlCall) node;
                final SqlNodeList selectList = new SqlNodeList(SqlParserPos.ZERO);
                selectList.add(SqlIdentifier.star(SqlParserPos.ZERO));
                return new SqlSelect(SqlParserPos.ZERO, null, selectList, call.operand(0), null, null, null, null, null, null, null, null);
            }
        case DELETE:
            {
                SqlDelete call = (SqlDelete) node;
                SqlSelect select = createSourceSelectForDelete(call);
                call.setSourceSelect(select);
                break;
            }
        case UPDATE:
            {
                SqlUpdate call = (SqlUpdate) node;
                SqlSelect select = createSourceSelectForUpdate(call);
                call.setSourceSelect(select);
                // in which case leave it alone).
                if (!validatingSqlMerge) {
                    SqlNode selfJoinSrcExpr = getSelfJoinExprForUpdate(call.getTargetTable(), UPDATE_SRC_ALIAS);
                    if (selfJoinSrcExpr != null) {
                        node = rewriteUpdateToMerge(call, selfJoinSrcExpr);
                    }
                }
                break;
            }
        case MERGE:
            {
                SqlMerge call = (SqlMerge) node;
                rewriteMerge(call);
                break;
            }
    }
    return node;
}
Also used : Ord(org.apache.calcite.linq4j.Ord) SqlCall(org.apache.calcite.sql.SqlCall) SqlOperator(org.apache.calcite.sql.SqlOperator) SqlWith(org.apache.calcite.sql.SqlWith) ArrayList(java.util.ArrayList) SqlKind(org.apache.calcite.sql.SqlKind) SqlUpdate(org.apache.calcite.sql.SqlUpdate) SqlMerge(org.apache.calcite.sql.SqlMerge) SqlSelect(org.apache.calcite.sql.SqlSelect) SqlBasicCall(org.apache.calcite.sql.SqlBasicCall) SqlDelete(org.apache.calcite.sql.SqlDelete) SqlNodeList(org.apache.calcite.sql.SqlNodeList) SqlOrderBy(org.apache.calcite.sql.SqlOrderBy) SqlNode(org.apache.calcite.sql.SqlNode) SqlUnresolvedFunction(org.apache.calcite.sql.SqlUnresolvedFunction)

Aggregations

ArrayList (java.util.ArrayList)2 Ord (org.apache.calcite.linq4j.Ord)2 SqlBasicCall (org.apache.calcite.sql.SqlBasicCall)2 SqlCall (org.apache.calcite.sql.SqlCall)2 SqlDelete (org.apache.calcite.sql.SqlDelete)2 SqlKind (org.apache.calcite.sql.SqlKind)2 SqlMerge (org.apache.calcite.sql.SqlMerge)2 SqlNode (org.apache.calcite.sql.SqlNode)2 SqlNodeList (org.apache.calcite.sql.SqlNodeList)2 SqlOperator (org.apache.calcite.sql.SqlOperator)2 SqlOrderBy (org.apache.calcite.sql.SqlOrderBy)2 SqlSelect (org.apache.calcite.sql.SqlSelect)2 SqlUnresolvedFunction (org.apache.calcite.sql.SqlUnresolvedFunction)2 SqlUpdate (org.apache.calcite.sql.SqlUpdate)2 SqlWith (org.apache.calcite.sql.SqlWith)2