// GetLogger returns a logger
func (dc *DefaultContainer) GetLogger() logger.Logger {
if dc.Logger == nil {
dc.Logger = logger.NewDefaultLogger()
}
return dc.Logger
}
func ExampleConnection() {
t := test.ExampleTester{log.New(os.Stderr, "log-tester", log.LstdFlags)}
// Define a type that represents a table
type TestUser struct {
ID int64 `sql:"column:id"`
Name string `sql:"column:name"` // db field name will match the content of the tag if declared
Email string `sql:"column:email"` // fieldnames are not automatically lower-cased to match db field names
Created time.Time `sql:"column:created"`
Nickname string `sql:"column:nick_name,persistzerovalue"` // allow empty strings or zero values to be persisted
PhoneNumbers []string `sql:"-"` // ignore field
}
var err error
// initialize the driver
DB, err := sql.Open("sqlite3", ":memory:")
test.Fatal(t, err, nil)
// create a connection
connection := db.NewConnection("sqlite3", DB)
connection.SetLogger(logger.NewDefaultLogger())
// create a table
_, err = connection.Exec(`
CREATE TABLE users(
id INTEGER PRIMARY KEY AUTOINCREMENT,
name VARCHAR(255) UNIQUE NOT NULL,
email VARCHAR(255) UNIQUE NOT NULL,
nick_name VARCHAR(255) NOT NULL,
created TIMESTAMP NOT NULL DEFAULT(datetime('now'))
);`)
test.Fatal(t, err, nil)
user := &TestUser{Name: "John Doe", Email: "*****@*****.**"}
// Insert a new user into the database
result, err := connection.Insert("users", user)
test.Fatal(t, err, nil)
id, err := result.LastInsertId()
test.Fatal(t, err, nil)
fmt.Println("last inserted id", id)
// insert another user thanks to the query builder
result, err = connection.CreateQueryBuilder().
Insert("users").
SetValue("name", "?").
SetValue("email", "?").
SetValue("nick_name", "?").
Exec("Jane Doe", "*****@*****.**", "Jannie")
test.Fatal(t, err, nil)
// fetch the first inserted user
candidate := &TestUser{}
err = connection.QueryRow("SELECT u.* FROM users u WHERE u.id = ?", id).
GetResult(candidate)
test.Fatal(t, err, nil)
fmt.Println("candidate.Name:", candidate.Name)
// update the record
candidate.Name = "John Robert Doe"
result, err = connection.Update("users", map[string]interface{}{"id": candidate.ID}, candidate)
test.Fatal(t, err, nil)
affectedRows, err := result.RowsAffected()
test.Fatal(t, err, nil)
fmt.Println("rows affected by update:", affectedRows)
// delete the record
result, err = connection.Delete("users", map[string]interface{}{"id": candidate.ID})
test.Fatal(t, err, nil)
affectedRows, err = result.RowsAffected()
test.Fatal(t, err, nil)
fmt.Println("rows affected by delete:", affectedRows)
// let' make sure there is only one user in the database
var count int
err = connection.CreateQueryBuilder().
Select("COUNT(u.id)").From("users", "u").
QueryRow().
GetSingleResult(&count)
test.Fatal(t, err, nil)
fmt.Println("user count:", count)
// Output:
// last inserted id 1
// candidate.Name: John Doe
// rows affected by update: 1
// rows affected by delete: 1
// user count: 1
}