mirror of
https://github.com/rocky-linux/peridot.git
synced 2024-12-24 19:38:31 +00:00
214 lines
8.4 KiB
Markdown
214 lines
8.4 KiB
Markdown
# sqlx
|
|
|
|
[](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)
|
|
|
|
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 [user documentation](http://jmoiron.github.io/sqlx/) that
|
|
explains how to use `database/sql` along with sqlx.
|
|
|
|
## Recent Changes
|
|
|
|
1.3.0:
|
|
|
|
* `sqlx.DB.Connx(context.Context) *sqlx.Conn`
|
|
* `sqlx.BindDriver(driverName, bindType)`
|
|
* support for `[]map[string]interface{}` to do "batch" insertions
|
|
* allocation & perf improvements for `sqlx.In`
|
|
|
|
DB.Connx returns an `sqlx.Conn`, which is an `sql.Conn`-alike consistent with
|
|
sqlx's wrapping of other types.
|
|
|
|
`BindDriver` allows users to control the bindvars that sqlx will use for drivers,
|
|
and add new drivers at runtime. This results in a very slight performance hit
|
|
when resolving the driver into a bind type (~40ns per call), but it allows users
|
|
to specify what bindtype their driver uses even when sqlx has not been updated
|
|
to know about it by default.
|
|
|
|
### Backwards Compatibility
|
|
|
|
Compatibility with the most recent two versions of Go is a requirement for any
|
|
new changes. Compatibility beyond that is not guaranteed.
|
|
|
|
Versioning is done with Go modules. Breaking changes (eg. removing deprecated API)
|
|
will get major version number bumps.
|
|
|
|
## 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
|
|
// 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)
|
|
|
|
|
|
// batch insert
|
|
|
|
// batch insert with structs
|
|
personStructs := []Person{
|
|
{FirstName: "Ardie", LastName: "Savea", Email: "asavea@ab.co.nz"},
|
|
{FirstName: "Sonny Bill", LastName: "Williams", Email: "sbw@ab.co.nz"},
|
|
{FirstName: "Ngani", LastName: "Laumape", Email: "nlaumape@ab.co.nz"},
|
|
}
|
|
|
|
_, err = db.NamedExec(`INSERT INTO person (first_name, last_name, email)
|
|
VALUES (:first_name, :last_name, :email)`, personStructs)
|
|
|
|
// batch insert with maps
|
|
personMaps := []map[string]interface{}{
|
|
{"first_name": "Ardie", "last_name": "Savea", "email": "asavea@ab.co.nz"},
|
|
{"first_name": "Sonny Bill", "last_name": "Williams", "email": "sbw@ab.co.nz"},
|
|
{"first_name": "Ngani", "last_name": "Laumape", "email": "nlaumape@ab.co.nz"},
|
|
}
|
|
|
|
_, err = db.NamedExec(`INSERT INTO person (first_name, last_name, email)
|
|
VALUES (:first_name, :last_name, :email)`, personMaps)
|
|
}
|
|
```
|