# Probando una Base de Datos { #testing-a-database }

Puedes estudiar sobre bases de datos, SQL y SQLModel en la <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">documentación de SQLModel</a>. 🤓

Hay un mini <a href="https://sqlmodel.tiangolo.com/tutorial/fastapi/" class="external-link" target="_blank">tutorial sobre el uso de SQLModel con FastAPI</a>. ✨

	err          *error
	readCloser   io.ReadCloser
	onReaderExit func()

	exitReader chan struct{}
	readerWg   sync.WaitGroup
}

// Read - reads single record.
func (r *Reader) Read(dst sql.Record) (sql.Record, error) {
	v, ok := <-r.decoded
	if !ok {
		if r.err != nil && *r.err != nil {
			return nil, errJSONParsingError(*r.err)
		}
		return nil, io.EOF
	}
	dstRec, ok := dst.(*Record)
	if !ok {

		if db.Error != nil {
			return
		}

		if db.Statement.Schema != nil {
			for _, c := range db.Statement.Schema.UpdateClauses {
				db.Statement.AddClause(c)
			}
		}

		if db.Statement.SQL.Len() == 0 {
			db.Statement.SQL.Grow(180)
			db.Statement.AddClauseIfNotExists(clause.Update{})
			if _, ok := db.Statement.Clauses["SET"]; !ok {
				if set := ConvertToAssignments(db.Statement); len(set) != 0 {

- ⚡ [**FastAPI**](https://fastapi.tiangolo.com) for the Python backend API.
  - 🧰 [SQLModel](https://sqlmodel.tiangolo.com) for the Python SQL database interactions (ORM).
  - 🔍 [Pydantic](https://docs.pydantic.dev), used by FastAPI, for the data validation and settings management.
  - 💾 [PostgreSQL](https://www.postgresql.org) as the SQL database.
- 🚀 [React](https://react.dev) for the frontend.

    - 🧰 [SQLModel](https://sqlmodel.tiangolo.com) para las interacciones con bases de datos SQL en Python (ORM).
    - 🔍 [Pydantic](https://docs.pydantic.dev), utilizado por FastAPI, para la validación de datos y gestión de configuraciones.
    - 💾 [PostgreSQL](https://www.postgresql.org) como base de datos SQL.
- 🚀 [React](https://react.dev) para el frontend.

			buildNames = append(buildNames, c.Name())
			buildNamesMap[c.Name()] = true
		}

		stmt.AddClause(c)
	}

	stmt.Build(buildNames...)

	if strings.TrimSpace(stmt.SQL.String()) != result {
		t.Errorf("SQL expects %v got %v", result, stmt.SQL.String())
	}

	if !reflect.DeepEqual(stmt.Vars, vars) {
		t.Errorf("Vars expects %+v got %v", stmt.Vars, vars)
	}

## FastAPI全栈模板 - 技术栈和特性

- ⚡ [**FastAPI**](https://fastapi.tiangolo.com) 用于Python后端API.
    - 🧰 [SQLModel](https://sqlmodel.tiangolo.com) 用于Python和SQL数据库的集成（ORM）。
    - 🔍 [Pydantic](https://docs.pydantic.dev) FastAPI的依赖项之一，用于数据验证和配置管理。
    - 💾 [PostgreSQL](https://www.postgresql.org) 作为SQL数据库。
- 🚀 [React](https://react.dev) 用于前端。
    - 💃 使用了TypeScript、hooks、[Vite](https://vitejs.dev)和其他一些现代化的前端技术栈。

		Logger: DB.Config.Logger,
		Test: func(ctx context.Context, begin time.Time, fc func() (sql string, rowsAffected int64), err error) {
			sql, _ := fc()
			if strings.HasPrefix(sql, "ALTER TABLE \"migrate_ints\" ALTER COLUMN \"int8\" TYPE smallint") {
				t.Fatalf("shouldn't execute ALTER COLUMN TYPE if such type is already existed in DB schema: sql: %s",
					sql)
			}
		},
	}

	DB.Migrator().DropTable(&MigrateInt{})

		for _, clause := range clauses {
			stmt.AddClause(clause)
		}

		stmt.Build("SELECT", "FROM", "WHERE")
		_ = stmt.SQL.String()
	}
}

func BenchmarkComplexSelect(b *testing.B) {
	user, _ := schema.Parse(&tests.User{}, &sync.Map{}, db.NamingStrategy)

	limit10 := 10
	for i := 0; i < b.N; i++ {

		}
		shiftDelimiter++
	}

	if continuousBacktick > 0 && !selfQuoted {
		writer.WriteString("``")
	}
	writer.WriteByte('`')
}

func (DummyDialector) Explain(sql string, vars ...interface{}) string {
	return logger.ExplainSQL(sql, nil, `"`, vars...)
}

func (DummyDialector) DataTypeOf(*schema.Field) string {
	return ""
}

func (d DummyDialector) Translate(err error) error {
	return d.TranslatedErr