public ColumnSchema getColumn(
      final String columnName, final TsTableColumnCategory columnCategory) {
    return columns.stream()
        .filter(
            column ->
                column.getName().equals(columnName) && column.getColumnCategory() == columnCategory)
        .findAny()
        .orElse(null);
  }
Get the column with the specified name and category, return null if not found.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/relational/metadata/TableSchema.java