ksql/examples/crud/crud.go

112 lines
2.2 KiB
Go

package main
import (
"context"
"fmt"
_ "github.com/mattn/go-sqlite3"
"github.com/vingarcia/kissorm"
"github.com/vingarcia/kissorm/nullable"
)
// User ...
type User struct {
ID int `kissorm:"id"`
Name string `kissorm:"name"`
Age int `kissorm:"age"`
}
// PartialUpdateUser ...
type PartialUpdateUser struct {
ID int `kissorm:"id"`
Name *string `kissorm:"name"`
Age *int `kissorm:"age"`
}
func main() {
ctx := context.Background()
db, err := kissorm.New("sqlite3", "/tmp/hello.sqlite", 1, "users")
if err != nil {
panic(err.Error())
}
err = db.Exec(ctx, `CREATE TABLE IF NOT EXISTS users (
id INTEGER PRIMARY KEY,
age INTEGER,
name TEXT
)`)
if err != nil {
panic(err.Error())
}
var alison = User{
Name: "Alison",
Age: 22,
}
err = db.Insert(ctx, &alison)
if err != nil {
panic(err.Error())
}
fmt.Println("Alison ID:", alison.ID)
// Inserting inline:
err = db.Insert(ctx, &User{
Name: "Cristina",
Age: 27,
})
if err != nil {
panic(err.Error())
}
// Deleting Alison:
err = db.Delete(ctx, alison.ID)
if err != nil {
panic(err.Error())
}
// Retrieving Cristina:
var cris User
err = db.QueryOne(ctx, &cris, "SELECT * FROM users WHERE name = ? ORDER BY id", "Cristina")
if err != nil {
panic(err.Error())
}
fmt.Printf("Cristina: %#v\n", cris)
// Updating all fields from Cristina:
cris.Name = "Cris"
err = db.Update(ctx, cris)
// Changing the age of Cristina but not touching any other fields:
// Partial update technique 1:
err = db.Update(ctx, struct {
ID int `kissorm:"id"`
Age int `kissorm:"age"`
}{ID: cris.ID, Age: 28})
if err != nil {
panic(err.Error())
}
// Partial update technique 2:
err = db.Update(ctx, PartialUpdateUser{
ID: cris.ID,
Age: nullable.Int(28),
})
if err != nil {
panic(err.Error())
}
// Listing first 10 users from the database
// (each time you run this example a new Cristina is created)
//
// Note: Using this function it is recommended to set a LIMIT, since
// not doing so can load too many users on your computer's memory or
// cause an Out Of Memory Kill.
var users []User
err = db.Query(ctx, &users, "SELECT * FROM users LIMIT 10")
if err != nil {
panic(err.Error())
}
fmt.Printf("Users: %#v\n", users)
}