sqlx is a library which provides a set of extensions on go's standard
database/sql
library. The sqlx versions of sql.DB
, sql.TX
, sql.Stmt
,
et al. all leave the underlying interfaces untouched, so that their interfaces
are a superset on the standard ones. This makes it relatively painless to
integrate existing codebases using database/sql with sqlx.
Major additional concepts are:
- Marshal rows into structs (with embedded struct support), maps, and slices
- Named parameter support including prepared statements
Get
andSelect
to go quickly from query to struct/slice
In addition to the godoc API documentation,
there is also some standard documentation that
explains how to use database/sql
along with sqlx.
- sqlx/types.JsonText has been renamed to JSONText to follow Go naming conventions.
This breaks backwards compatibility, but it's in a way that is trivially fixable
(s/JsonText/JSONText/g
). The types
package is both experimental and not in
active development currently.
- Using Go 1.6 and below with
types.JSONText
andtypes.GzippedText
can be potentially unsafe, especially when used with common auto-scan sqlx idioms likeSelect
andGet
. See golang bug #13905.
There is no Go1-like promise of absolute stability, but I take the issue seriously and will maintain the library in a compatible state unless vital bugs prevent me from doing so. Since #59 and #60 necessitated breaking behavior, a wider API cleanup was done at the time of fixing. It's possible this will happen in future; if it does, a git tag will be provided for users requiring the old behavior to continue to use it until such a time as they can migrate.
go get github.com/jmoiron/sqlx
Row headers can be ambiguous (SELECT 1 AS a, 2 AS a
), and the result of
Columns()
does not fully qualify column names in queries like:
SELECT a.id, a.name, b.id, b.name FROM foos AS a JOIN foos AS b ON a.parent = b.id;
making a struct or map destination ambiguous. Use AS
in your queries
to give columns distinct names, rows.Scan
to scan them manually, or
SliceScan
to get a slice of results.
Below is an example which shows some common use cases for sqlx. Check sqlx_test.go for more usage.
package main
import (
"database/sql"
"fmt"
"log"
_ "github.com/lib/pq"
"github.com/jmoiron/sqlx"
)
var schema = `
CREATE TABLE person (
first_name text,
last_name text,
email text
);
CREATE TABLE place (
country text,
city text NULL,
telcode integer
)`
type Person struct {
FirstName string `db:"first_name"`
LastName string `db:"last_name"`
Email string
}
type Place struct {
Country string
City sql.NullString
TelCode int
}
func main() {
// this Pings the database trying to connect, panics on error
// use sqlx.Open() for sql.Open() semantics
db, err := sqlx.Connect("postgres", "user=foo dbname=bar sslmode=disable")
if err != nil {
log.Fatalln(err)
}
// exec the schema or fail; multi-statement Exec behavior varies between
// database drivers; pq will exec them all, sqlite3 won't, ymmv
db.MustExec(schema)
tx := db.MustBegin()
tx.MustExec("INSERT INTO person (first_name, last_name, email) VALUES ($1, $2, $3)", "Jason", "Moiron", "jmoiron@jmoiron.net")
tx.MustExec("INSERT INTO person (first_name, last_name, email) VALUES ($1, $2, $3)", "John", "Doe", "johndoeDNE@gmail.net")
tx.MustExec("INSERT INTO place (country, city, telcode) VALUES ($1, $2, $3)", "United States", "New York", "1")
tx.MustExec("INSERT INTO place (country, telcode) VALUES ($1, $2)", "Hong Kong", "852")
tx.MustExec("INSERT INTO place (country, telcode) VALUES ($1, $2)", "Singapore", "65")
// Named queries can use structs, so if you have an existing struct (i.e. person := &Person{}) that you have populated, you can pass it in as &person
tx.NamedExec("INSERT INTO person (first_name, last_name, email) VALUES (:first_name, :last_name, :email)", &Person{"Jane", "Citizen", "jane.citzen@example.com"})
tx.Commit()
// Query the database, storing results in a []Person (wrapped in []interface{})
people := []Person{}
db.Select(&people, "SELECT * FROM person ORDER BY first_name ASC")
jason, john := people[0], people[1]
fmt.Printf("%#v\n%#v", jason, john)
// Person{FirstName:"Jason", LastName:"Moiron", Email:"jmoiron@jmoiron.net"}
// Person{FirstName:"John", LastName:"Doe", Email:"johndoeDNE@gmail.net"}
// You can also get a single result, a la QueryRow
jason = Person{}
err = db.Get(&jason, "SELECT * FROM person WHERE first_name=$1", "Jason")
fmt.Printf("%#v\n", jason)
// Person{FirstName:"Jason", LastName:"Moiron", Email:"jmoiron@jmoiron.net"}
// if you have null fields and use SELECT *, you must use sql.Null* in your struct
places := []Place{}
err = db.Select(&places, "SELECT * FROM place ORDER BY telcode ASC")
if err != nil {
fmt.Println(err)
return
}
usa, singsing, honkers := places[0], places[1], places[2]
fmt.Printf("%#v\n%#v\n%#v\n", usa, singsing, honkers)
// Place{Country:"United States", City:sql.NullString{String:"New York", Valid:true}, TelCode:1}
// Place{Country:"Singapore", City:sql.NullString{String:"", Valid:false}, TelCode:65}
// Place{Country:"Hong Kong", City:sql.NullString{String:"", Valid:false}, TelCode:852}
// Loop through rows using only one struct
place := Place{}
rows, err := db.Queryx("SELECT * FROM place")
for rows.Next() {
err := rows.StructScan(&place)
if err != nil {
log.Fatalln(err)
}
fmt.Printf("%#v\n", place)
}
// Place{Country:"United States", City:sql.NullString{String:"New York", Valid:true}, TelCode:1}
// Place{Country:"Hong Kong", City:sql.NullString{String:"", Valid:false}, TelCode:852}
// Place{Country:"Singapore", City:sql.NullString{String:"", Valid:false}, TelCode:65}
// Named queries, using `:name` as the bindvar. Automatic bindvar support
// which takes into account the dbtype based on the driverName on sqlx.Open/Connect
_, err = db.NamedExec(`INSERT INTO person (first_name,last_name,email) VALUES (:first,:last,:email)`,
map[string]interface{}{
"first": "Bin",
"last": "Smuth",
"email": "bensmith@allblacks.nz",
})
// Selects Mr. Smith from the database
rows, err = db.NamedQuery(`SELECT * FROM person WHERE first_name=:fn`, map[string]interface{}{"fn": "Bin"})
// Named queries can also use structs. Their bind names follow the same rules
// as the name -> db mapping, so struct fields are lowercased and the `db` tag
// is taken into consideration.
rows, err = db.NamedQuery(`SELECT * FROM person WHERE first_name=:first_name`, jason)
}