fixes

internal/xsql/conn.go

@@ -33,6 +33,8 @@ var (
 
 type (
 	connWrapper struct {
+		processor Engine
+
 		cc        conn.Conn
 		currentTx *txWrapper
 
@@ -45,6 +47,10 @@ type (
 	}
 )
 
+func (c *connWrapper) Engine() Engine {
+	return c.processor
+}
+
 func (c *connWrapper) Ping(ctx context.Context) error {
 	return c.cc.Ping(ctx)
 }
@@ -82,6 +88,10 @@ func (c *connWrapper) Close() error {
 	return nil
 }
 
+func (c *connWrapper) Connector() *Connector {
+	return c.connector
+}
+
 func (c *connWrapper) Begin() (driver.Tx, error) {
 	return nil, xerrors.WithStackTrace(errDeprecated)
 }

internal/xsql/conn/query/errors.go

@@ -10,6 +10,6 @@ import (
 var (
 	ErrUnsupported     = driver.ErrSkip
 	errDeprecated      = driver.ErrSkip
-	errConnClosedEarly = xerrors.Retryable(errors.New("Conn closed early"), xerrors.InvalidObject())
-	errNotReadyConn    = xerrors.Retryable(errors.New("Conn not ready"), xerrors.InvalidObject())
+	errConnClosedEarly = xerrors.Retryable(errors.New("conn closed early"), xerrors.InvalidObject())
+	errNotReadyConn    = xerrors.Retryable(errors.New("conn not ready"), xerrors.InvalidObject())
 )

internal/xsql/connector.go

@@ -5,6 +5,7 @@ import (
 	"database/sql/driver"
 	"io"
 	"os"
+	"strconv"
 	"time"
 
 	"github.com/google/uuid"
@@ -31,12 +32,12 @@ var (
 )
 
 type (
-	queryProcessor uint8
-	Connector      struct {
+	Engine    uint8
+	Connector struct {
 		parent   ydbDriver
 		balancer grpc.ClientConnInterface
 
-		queryProcessor queryProcessor
+		processor Engine
 
 		TableOpts             []connOverTableServiceClient.Option
 		QueryOpts             []connOverQueryServiceClient.Option
@@ -112,7 +113,7 @@ func (c *Connector) Open(name string) (driver.Conn, error) {
 }
 
 func (c *Connector) Connect(ctx context.Context) (driver.Conn, error) {
-	switch c.queryProcessor {
+	switch c.processor {
 	case QUERY_SERVICE:
 		s, err := query.CreateSession(ctx, c.Query())
 		if err != nil {
@@ -122,6 +123,7 @@ func (c *Connector) Connect(ctx context.Context) (driver.Conn, error) {
 		id := uuid.New()
 
 		conn := &connWrapper{
+			processor: QUERY_SERVICE,
 			cc: connOverQueryServiceClient.New(ctx, c, s, append(
 				c.QueryOpts,
 				connOverQueryServiceClient.WithOnClose(func() {
@@ -145,6 +147,7 @@ func (c *Connector) Connect(ctx context.Context) (driver.Conn, error) {
 		id := uuid.New()
 
 		conn := &connWrapper{
+			processor: TABLE_SERVICE,
 			cc: connOverTableServiceClient.New(ctx, c, s, append(c.TableOpts,
 				connOverTableServiceClient.WithOnClose(func() {
 					c.conns.Delete(id)
@@ -189,8 +192,8 @@ func Open(parent ydbDriver, balancer grpc.ClientConnInterface, opts ...Option) (
 	c := &Connector{
 		parent:   parent,
 		balancer: balancer,
-		queryProcessor: func() queryProcessor {
-			if v, has := os.LookupEnv("YDB_DATABASE_SQL_OVER_QUERY_SERVICE"); has && v != "" {
+		processor: func() Engine {
+			if overQueryService, _ := strconv.ParseBool(os.Getenv("YDB_DATABASE_SQL_OVER_QUERY_SERVICE")); overQueryService {
 				return QUERY_SERVICE
 			}
 

internal/xsql/options.go

@@ -41,7 +41,7 @@ type (
 	bindOption struct {
 		bind.Bind
 	}
-	queryProcessorOption queryProcessor
+	queryProcessorOption Engine
 )
 
 func (t tablePathPrefixOption) Apply(c *Connector) error {
@@ -52,7 +52,7 @@ func (t tablePathPrefixOption) Apply(c *Connector) error {
 }
 
 func (processor queryProcessorOption) Apply(c *Connector) error {
-	c.queryProcessor = queryProcessor(processor)
+	c.processor = Engine(processor)
 
 	return nil
 }

retry/sql.go

@@ -40,7 +40,7 @@ func WithDoRetryOptions(opts ...Option) doRetryOptionsOption {
 	return opts
 }
 
-// Do is a retryer of database/sql Conn with fallbacks on errors
+// Do is a retryer of database/sql conn with fallbacks on errors
 func Do(ctx context.Context, db *sql.DB, op func(ctx context.Context, cc *sql.Conn) error, opts ...doOption) error {
 	_, err := DoWithResult(ctx, db, func(ctx context.Context, cc *sql.Conn) (*struct{}, error) {
 		err := op(ctx, cc)
@@ -57,7 +57,7 @@ func Do(ctx context.Context, db *sql.DB, op func(ctx context.Context, cc *sql.Co
 	return nil
 }
 
-// DoWithResult is a retryer of database/sql Conn with fallbacks on errors
+// DoWithResult is a retryer of database/sql conn with fallbacks on errors
 //
 // Experimental: https://github.com/ydb-platform/ydb-go-sdk/blob/master/VERSIONING.md#experimental
 func DoWithResult[T any](ctx context.Context, db *sql.DB,

sql.go

@@ -141,6 +141,14 @@ func WithDefaultQueryMode(mode QueryMode) ConnectorOption {
 	)
 }
 
+// OverQueryService is an experimental flag for create database/sql driver over query service client
+//
+// By default database/sql driver works over table service client
+// Default will be changed to `OverQueryService` after March 2025
+func OverQueryService() ConnectorOption {
+	return xsql.OverQueryService()
+}
+
 func WithFakeTx(modes ...QueryMode) ConnectorOption {
 	opts := make([]ConnectorOption, 0, len(modes))
 

tests/integration/helpers_test.go

@@ -21,6 +21,7 @@ import (
 
 	"github.com/ydb-platform/ydb-go-sdk/v3"
 	"github.com/ydb-platform/ydb-go-sdk/v3/config"
+	"github.com/ydb-platform/ydb-go-sdk/v3/internal/xsql"
 	"github.com/ydb-platform/ydb-go-sdk/v3/internal/xsync"
 	"github.com/ydb-platform/ydb-go-sdk/v3/internal/xtest"
 	"github.com/ydb-platform/ydb-go-sdk/v3/log"
@@ -443,3 +444,26 @@ func (t *testLogger) flush() {
 		t.test.Log(message)
 	})
 }
+
+func driverEngine(db *sql.DB) (engine xsql.Engine) {
+	cc, err := db.Conn(context.Background())
+	if err != nil {
+		return engine
+	}
+
+	defer func() {
+		_ = cc.Close()
+	}()
+
+	cc.Raw(func(driverConn any) error {
+		if ccc, has := driverConn.(interface {
+			Engine() xsql.Engine
+		}); has {
+			engine = ccc.Engine()
+		}
+
+		return nil
+	})
+
+	return engine
+}

tests/integration/table_truncated_err_test.go

@@ -11,6 +11,7 @@ import (
 	"testing"
 
 	"github.com/ydb-platform/ydb-go-sdk/v3"
+	"github.com/ydb-platform/ydb-go-sdk/v3/internal/xsql"
 	"github.com/ydb-platform/ydb-go-sdk/v3/retry"
 	"github.com/ydb-platform/ydb-go-sdk/v3/table"
 	"github.com/ydb-platform/ydb-go-sdk/v3/table/options"
@@ -133,7 +134,12 @@ func TestIssue798TruncatedError(t *testing.T) {
 			}
 			return rows.Err()
 		}, retry.WithIdempotent(true))
-		scope.Require.ErrorIs(err, result.ErrTruncated)
+		switch driverEngine(db) {
+		case xsql.TABLE_SERVICE:
+			scope.Require.ErrorIs(err, result.ErrTruncated)
+		case xsql.QUERY_SERVICE:
+			scope.Require.NoError(err)
+		}
 	}
 
 	// select all rows without truncated result error