[feature](vectorized) support vexplode_bitmap (#8890)

be/src/vec/exprs/table_function/vexplode_bitmap.cpp

@@ -0,0 +1,81 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#include "vec/exprs/table_function/vexplode_bitmap.h"
+
+#include "util/bitmap_value.h"
+#include "vec/exprs/vexpr.h"
+
+namespace doris::vectorized {
+
+VExplodeBitmapTableFunction::VExplodeBitmapTableFunction() {
+    _fn_name = "vexplode_bitmap";
+}
+
+Status VExplodeBitmapTableFunction::process_init(vectorized::Block* block) {
+    CHECK(_vexpr_context->root()->children().size() == 1)
+            << "VExplodeNumbersTableFunction must be have 1 children but have "
+            << _vexpr_context->root()->children().size();
+
+    int value_column_idx = -1;
+    _vexpr_context->root()->children()[0]->execute(_vexpr_context, block, &value_column_idx);
+    _value_column = block->get_by_position(value_column_idx).column;
+
+    return Status::OK();
+}
+
+Status VExplodeBitmapTableFunction::process_row(size_t row_idx) {
+    _eos = false;
+    _is_current_empty = false;
+    _cur_size = 0;
+    _cur_offset = 0;
+
+    StringRef value = _value_column->get_data_at(row_idx);
+
+    if (value.data == nullptr) {
+        _is_current_empty = true;
+    } else {
+        _cur_bitmap = reinterpret_cast<const BitmapValue*>(value.data);
+        _cur_bitmap_owned = false;
+
+        _cur_size = _cur_bitmap->cardinality();
+        if (_cur_size == 0) {
+            _is_current_empty = true;
+        } else {
+            _reset_iterator();
+        }
+    }
+
+    _is_current_empty = (_cur_size == 0);
+    return Status::OK();
+}
+
+Status VExplodeBitmapTableFunction::process_close() {
+    _value_column = nullptr;
+    return Status::OK();
+}
+
+Status VExplodeBitmapTableFunction::get_value_length(int64_t* length) {
+    if (_is_current_empty) {
+        *length = -1;
+    } else {
+        *length = sizeof(uint64_t);
+    }
+    return Status::OK();
+}
+
+} // namespace doris::vectorized