feat: migrator support type aliases (#5627)

* feat: migrator support type aliases

* perf: check type

gorm.go

@@ -248,10 +248,18 @@ func (db *DB) Session(config *Session) *DB {
 	if config.PrepareStmt {
 		if v, ok := db.cacheStore.Load(preparedStmtDBKey); ok {
 			preparedStmt := v.(*PreparedStmtDB)
-			tx.Statement.ConnPool = &PreparedStmtDB{
-				ConnPool: db.Statement.ConnPool,
-				Mux:      preparedStmt.Mux,
-				Stmts:    preparedStmt.Stmts,
+			switch t := tx.Statement.ConnPool.(type) {
+			case Tx:
+				tx.Statement.ConnPool = &PreparedStmtTX{
+					Tx:             t,
+					PreparedStmtDB: preparedStmt,
+				}
+			default:
+				tx.Statement.ConnPool = &PreparedStmtDB{
+					ConnPool: db.Config.ConnPool,
+					Mux:      preparedStmt.Mux,
+					Stmts:    preparedStmt.Stmts,
+				}
 			}
 			txConfig.ConnPool = tx.Statement.ConnPool
 			txConfig.PrepareStmt = true

migrator.go

@@ -68,6 +68,7 @@ type Migrator interface {
 	// Database
 	CurrentDatabase() string
 	FullDataTypeOf(*schema.Field) clause.Expr
+	GetTypeAliases(databaseTypeName string) []string
 
 	// Tables
 	CreateTable(dst ...interface{}) error

migrator/migrator.go

@@ -408,9 +408,27 @@ func (m Migrator) MigrateColumn(value interface{}, field *schema.Field, columnTy
 
 	alterColumn := false
 
-	// check type
-	if !field.PrimaryKey && !strings.HasPrefix(fullDataType, realDataType) {
-		alterColumn = true
+	if !field.PrimaryKey {
+		// check type
+		var isSameType bool
+		if strings.HasPrefix(fullDataType, realDataType) {
+			isSameType = true
+		}
+
+		// check type aliases
+		if !isSameType {
+			aliases := m.DB.Migrator().GetTypeAliases(realDataType)
+			for _, alias := range aliases {
+				if strings.HasPrefix(fullDataType, alias) {
+					isSameType = true
+					break
+				}
+			}
+		}
+
+		if !isSameType {
+			alterColumn = true
+		}
 	}
 
 	// check size
@@ -863,3 +881,8 @@ func (m Migrator) CurrentTable(stmt *gorm.Statement) interface{} {
 func (m Migrator) GetIndexes(dst interface{}) ([]gorm.Index, error) {
 	return nil, errors.New("not support")
 }
+
+// GetTypeAliases return database type aliases
+func (m Migrator) GetTypeAliases(databaseTypeName string) []string {
+	return nil
+}

tests/prepared_stmt_test.go

@@ -2,6 +2,7 @@ package tests_test
 
 import (
 	"context"
+	"errors"
 	"testing"
 	"time"
 
@@ -88,3 +89,19 @@ func TestPreparedStmtFromTransaction(t *testing.T) {
 	}
 	tx2.Commit()
 }
+
+func TestPreparedStmtInTransaction(t *testing.T) {
+	user := User{Name: "jinzhu"}
+
+	if err := DB.Transaction(func(tx *gorm.DB) error {
+		tx.Session(&gorm.Session{PrepareStmt: true}).Create(&user)
+		return errors.New("test")
+	}); err == nil {
+		t.Error(err)
+	}
+
+	var result User
+	if err := DB.First(&result, user.ID).Error; err == nil {
+		t.Errorf("Failed, got error: %v", err)
+	}
+}