use of org.apache.calcite.linq4j.Ord 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;
}
use of org.apache.calcite.linq4j.Ord 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;
}
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