Skip to content

Commit

Permalink
fix format
Browse files Browse the repository at this point in the history
  • Loading branch information
hongyunyan committed Jun 14, 2022
1 parent c4279e6 commit 3f3b101
Showing 1 changed file with 1 addition and 1 deletion.
2 changes: 1 addition & 1 deletion dbms/src/TiDB/Schema/SchemaBuilder.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -371,7 +371,7 @@ void SchemaBuilder<Getter, NameMapper>::applyAlterPhysicalTable(DBInfoPtr db_inf
/// Update column infos by applying schema change in this step.
schema_change.second(orig_table_info);
/// Update schema version aggressively for the sake of correctness(for read part).
/// In read action, we will use table_info.schema_version(storage_version) and TiDBSchemaSyncer.cur_version(global_version) to compare with query_version, to decide whether we can read under this query_version, or we need to make the schema newer.
/// In read action, we will use table_info.schema_version(storage_version) and TiDBSchemaSyncer.cur_version(global_version) to compare with query_version, to decide whether we can read under this query_version, or we need to make the schema newer.
/// In our comparison logic, we only serve the query when the query schema version meet the criterion: storage_version <= query_version <= global_version(The more detail info you can refer the comments in DAGStorageInterpreter::getAndLockStorages.)
/// And when apply multi diffs here, we only update global_version when all diffs have been applied.
/// So the global_version may be less than the actual "global_version" of the local schema in the process of applying schema changes.
Expand Down

0 comments on commit 3f3b101

Please sign in to comment.