First pass at batched database interface

Signed-off-by: Zach Musgrave <zach@liquidata.co>

go/libraries/doltcore/sqle/database.go

@@ -37,19 +37,33 @@ const (
 
 // Database implements sql.Database for a dolt DB.
 type Database struct {
-	sql.Database
-	name string
-	root *doltdb.RootValue
-	dEnv *env.DoltEnv
-	batchMode batchMode
+	name              string
+	root              *doltdb.RootValue
+	dEnv              *env.DoltEnv
+	batchMode         batchMode
+	outstandingTables map[string]*DoltTable
 }
 
 // NewDatabase returns a new dolt database to use in queries.
 func NewDatabase(name string, root *doltdb.RootValue, dEnv *env.DoltEnv) *Database {
 	return &Database{
-		name: name,
-		root: root,
-		dEnv: dEnv,
+		name:              name,
+		root:              root,
+		dEnv:              dEnv,
+		batchMode:         single,
+		outstandingTables: make(map[string]*DoltTable),
+	}
+}
+
+// NewBatchedDatabase returns a new dolt database executing in batch insert mode. Integrators must call Flush() to
+// commit any outstanding edits.
+func NewBatchedDatabase(name string, root *doltdb.RootValue, dEnv *env.DoltEnv) *Database {
+	return &Database{
+		name:              name,
+		root:              root,
+		dEnv:              dEnv,
+		batchMode:         batched,
+		outstandingTables: make(map[string]*DoltTable),
 	}
 }
 
@@ -101,7 +115,12 @@ func (db *Database) GetTableInsensitive(ctx context.Context, tblName string) (sq
 		return nil, false, err
 	}
 
-	return &DoltTable{name: tblName, table: tbl, sch: sch, db: db}, true, nil
+	table := &DoltTable{name: tblName, table: tbl, sch: sch, db: db}
+	if db.batchMode == batched {
+		db.outstandingTables[tblName] = table
+	}
+
+	return table, true, nil
 }
 
 func (db *Database) GetTableNames(ctx context.Context) ([]string, error) {
@@ -183,3 +202,13 @@ func (db *Database) CreateTable(ctx *sql.Context, tableName string, schema sql.S
 
 	return nil
 }
+
+// Flushes the current batch of outstanding changes and returns any errors.
+func (db *Database) Flush(ctx context.Context) error {
+	for _, table := range db.outstandingTables {
+		if err := table.flushBatchedEdits(ctx); err != nil {
+			return err
+		}
+	}
+	return nil
+}