Implemented dolt_history_dolt_schemas and dolt_diff_dolt_schemas

go/libraries/doltcore/doltdb/system_table.go

@@ -291,6 +291,42 @@ const (
 	// SchemasTablesSqlModeCol is the name of the column that stores the SQL_MODE string used when this fragment
 	// was originally defined. Mode settings, such as ANSI_QUOTES, are needed to correctly parse the fragment.
 	SchemasTablesSqlModeCol = "sql_mode"
+
+	// DiffTypeCol is the column name for the type of change (added, modified, removed) in diff tables
+	DiffTypeCol = "diff_type"
+
+	// ToCommitCol is the column name for the "to" commit in diff tables
+	ToCommitCol = "to_commit"
+
+	// FromCommitCol is the column name for the "from" commit in diff tables
+	FromCommitCol = "from_commit"
+
+	// ToCommitDateCol is the column name for the "to" commit date in diff tables
+	ToCommitDateCol = "to_commit_date"
+
+	// FromCommitDateCol is the column name for the "from" commit date in diff tables
+	FromCommitDateCol = "from_commit_date"
+
+	// WorkingCommitRef is the special commit reference for working changes
+	WorkingCommitRef = "WORKING"
+
+	// EmptyCommitRef is the special commit reference for empty/initial state
+	EmptyCommitRef = "EMPTY"
+
+	// DiffTypeAdded represents a row that was added in a diff
+	DiffTypeAdded = "added"
+
+	// DiffTypeModified represents a row that was modified in a diff
+	DiffTypeModified = "modified"
+
+	// DiffTypeRemoved represents a row that was removed in a diff
+	DiffTypeRemoved = "removed"
+
+	// DiffToPrefix is the prefix for "to" columns in diff tables
+	DiffToPrefix = "to_"
+
+	// DiffFromPrefix is the prefix for "from" columns in diff tables
+	DiffFromPrefix = "from_"
 )
 
 const (

go/libraries/doltcore/sqle/database.go

@@ -332,6 +332,20 @@ func (db Database) getTableInsensitive(ctx *sql.Context, head *doltdb.Commit, ds
 	// TODO: these tables that cache a root value at construction time should not, they need to get it from the session
 	//  at runtime
 	switch {
+	case lwrName == doltdb.DoltDiffTablePrefix+doltdb.SchemasTableName:
+		// Special handling for dolt_diff_dolt_schemas
+		// Get the HEAD commit
+		if head == nil {
+			var err error
+			head, err = ds.GetHeadCommit(ctx, db.RevisionQualifiedName())
+			if err != nil {
+				return nil, false, err
+			}
+		}
+
+		// Use the same pattern as regular diff tables - this will show complete history
+		return DoltSchemasDiffTable(ctx, db.ddb, head, root, db), true, nil
+
 	case strings.HasPrefix(lwrName, doltdb.DoltDiffTablePrefix):
 		if head == nil {
 			var err error
@@ -384,6 +398,17 @@ func (db Database) getTableInsensitive(ctx *sql.Context, head *doltdb.Commit, ds
 		}
 		return dt, true, nil
 
+	case lwrName == doltdb.DoltHistoryTablePrefix+doltdb.SchemasTableName:
+		// Special handling for dolt_history_dolt_schemas
+		if head == nil {
+			var err error
+			head, err = ds.GetHeadCommit(ctx, db.RevisionQualifiedName())
+			if err != nil {
+				return nil, false, err
+			}
+		}
+		return DoltSchemasHistoryTable(db.ddb, head, db), true, nil
+
 	case strings.HasPrefix(lwrName, doltdb.DoltHistoryTablePrefix):
 		baseTableName := tblName[len(doltdb.DoltHistoryTablePrefix):]
 		baseTable, ok, err := db.getTable(ctx, root, baseTableName)