use of org.apache.phoenix.parse.TableNode in project phoenix by apache.
the class QueryOptimizer method rewriteQueryWithIndexReplacement.
private static SelectStatement rewriteQueryWithIndexReplacement(final PhoenixConnection connection, final ColumnResolver resolver, final SelectStatement select, final Map<TableRef, TableRef> replacement) throws SQLException {
TableNode from = select.getFrom();
TableNode newFrom = from.accept(new TableNodeVisitor<TableNode>() {
private TableRef resolveTable(String alias, TableName name) throws SQLException {
if (alias != null)
return resolver.resolveTable(null, alias);
return resolver.resolveTable(name.getSchemaName(), name.getTableName());
}
private TableName getReplacedTableName(TableRef tableRef) {
String schemaName = tableRef.getTable().getSchemaName().getString();
return TableName.create(schemaName.length() == 0 ? null : schemaName, tableRef.getTable().getTableName().getString());
}
@Override
public TableNode visit(BindTableNode boundTableNode) throws SQLException {
TableRef tableRef = resolveTable(boundTableNode.getAlias(), boundTableNode.getName());
TableRef replaceRef = replacement.get(tableRef);
if (replaceRef == null)
return boundTableNode;
String alias = boundTableNode.getAlias();
return FACTORY.bindTable(alias == null ? null : '"' + alias + '"', getReplacedTableName(replaceRef));
}
@Override
public TableNode visit(JoinTableNode joinNode) throws SQLException {
TableNode lhs = joinNode.getLHS();
TableNode rhs = joinNode.getRHS();
TableNode lhsReplace = lhs.accept(this);
TableNode rhsReplace = rhs.accept(this);
if (lhs == lhsReplace && rhs == rhsReplace)
return joinNode;
return FACTORY.join(joinNode.getType(), lhsReplace, rhsReplace, joinNode.getOnNode(), joinNode.isSingleValueOnly());
}
@Override
public TableNode visit(NamedTableNode namedTableNode) throws SQLException {
TableRef tableRef = resolveTable(namedTableNode.getAlias(), namedTableNode.getName());
TableRef replaceRef = replacement.get(tableRef);
if (replaceRef == null)
return namedTableNode;
String alias = namedTableNode.getAlias();
return FACTORY.namedTable(alias == null ? null : '"' + alias + '"', getReplacedTableName(replaceRef), namedTableNode.getDynamicColumns(), namedTableNode.getTableSamplingRate());
}
@Override
public TableNode visit(DerivedTableNode subselectNode) throws SQLException {
return subselectNode;
}
});
if (from == newFrom) {
return select;
}
SelectStatement indexSelect = IndexStatementRewriter.translate(FACTORY.select(select, newFrom), resolver, replacement);
for (TableRef indexTableRef : replacement.values()) {
// replace expressions with corresponding matching columns for functional indexes
indexSelect = ParseNodeRewriter.rewrite(indexSelect, new IndexExpressionParseNodeRewriter(indexTableRef.getTable(), indexTableRef.getTableAlias(), connection, indexSelect.getUdfParseNodes()));
}
return indexSelect;
}
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