NewChecker creates a Checker.

NewInfoStore creates a InfoStore.

NewSchemaTracker creates a SchemaTracker.

NewStorageDDLInjector creates a new StorageDDLInjector to inject Checker.

UnwrapStorage unwraps StorageDDLInjector for one level.

ConstructResultOfShowCreateDatabase should be assigned to executor.ConstructResultOfShowCreateDatabase.

ConstructResultOfShowCreateTable should be assigned to executor.ConstructResultOfShowCreateTable.

Checker is used to check the result of SchemaTracker is same as real DDL.

InfoStore is a simple structure that stores DBInfo and TableInfo.

InfoStoreAdaptor convert InfoStore to InfoSchema, it only implements a part of InfoSchema interface to be used by DDL interface.

SchemaTracker is used to track schema changes by DM.

StorageDDLInjector wraps kv.Storage to inject checker to domain's DDL in bootstrap time.