Examples with SqlWith org.apache.calcite.sql.SqlWith used on opensource projects

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;
}

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;
}