2018-01-29 19:44:18 +00:00
# sqlx
2018-09-05 15:36:14 +00:00
[](https://travis-ci.org/jmoiron/sqlx) [](https://coveralls.io/github/jmoiron/sqlx?branch=master) [](https://godoc.org/github.com/jmoiron/sqlx) [](https://raw.githubusercontent.com/jmoiron/sqlx/master/LICENSE)
2018-01-29 19:44:18 +00:00
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` and `Select` to go quickly from query to struct/slice
In addition to the [godoc API documentation ](http://godoc.org/github.com/jmoiron/sqlx ),
there is also some [standard documentation ](http://jmoiron.github.io/sqlx/ ) that
explains how to use `database/sql` along with sqlx.
## Recent Changes
* 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` and `types.GzippedText` can be _potentially unsafe_ , **especially** when used with common auto-scan sqlx idioms like `Select` and `Get` . See [golang bug #13905 ](https://github.com/golang/go/issues/13905 ).
### Backwards Compatibility
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 ](https://github.com/jmoiron/sqlx/issues/59 ) and
[#60 ](https://github.com/jmoiron/sqlx/issues/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.
## install
go get github.com/jmoiron/sqlx
## issues
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:
```sql
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.
## usage
Below is an example which shows some common use cases for sqlx. Check
[sqlx_test.go ](https://github.com/jmoiron/sqlx/blob/master/sqlx_test.go ) for more
usage.
```go
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)
}
```
