Documentation

Overview

Package rsqldrv registers a database/sql/driver.Driver implementation for ROOT files.

Index

• func Connector(file *riofs.File) driver.Connector
• func Create(name string) (*sql.DB, error)
• func Open(name string) (*sql.DB, error)
• func OpenDB(file *riofs.File) *sql.DB

Examples

• Open
• Open (Connector)
• Open (Tuple)
• Open (WhereStmt)

Constants

This section is empty.

Variables

This section is empty.

Functions

func Connector

func Connector(file *riofs.File) driver.Connector

Connector returns a database/sql/driver.Connector from a ROOT file.

Connector can be used to open a database/sql.DB from an already open ROOT file.

func Create

func Create(name string) (*sql.DB, error)

Create is a ROOT/SQL-driver helper function for sql.Open.

It creates a new ROOT file, connected via the ROOT/SQL driver.

func Open

func Open(name string) (*sql.DB, error)

Open is a ROOT/SQL-driver helper function for sql.Open.

It opens a database connection to the ROOT/SQL driver.

Example

package main import ( "database/sql" "fmt" "log" ) func main() { db, err := sql.Open("root", "../../testdata/simple.root") if err != nil { log.Fatal(err) } defer db.Close() rows, err := db.Query("SELECT * FROM tree") if err != nil { log.Fatal(err) } defer rows.Close() type data struct { i32 int32 f32 float32 str string } n := 0 for rows.Next() { var v data err := rows.Scan(&v.i32, &v.f32, &v.str) if err != nil { log.Fatal(err) } fmt.Printf("row[%d]: (%v, %v, %q)\n", n, v.i32, v.f32, v.str) n++ } }

Output:

row[0]: (1, 1.1, "uno")
row[1]: (2, 2.2, "dos")
row[2]: (3, 3.3, "tres")
row[3]: (4, 4.4, "quatro")

Example (Connector)

package main import ( "database/sql" "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rsql/rsqldrv" "go-hep.org/x/hep/groot/rtree" ) func main() { f, err := groot.Open("../../testdata/simple.root") if err != nil { log.Fatal(err) } defer f.Close() o, err := f.Get("tree") if err != nil { log.Fatal(err) } tree := o.(rtree.Tree) db := sql.OpenDB(rsqldrv.Connector(rtree.FileOf(tree))) defer db.Close() rows, err := db.Query("SELECT * FROM tree") if err != nil { log.Fatal(err) } defer rows.Close() type data struct { i32 int32 f32 float32 str string } n := 0 for rows.Next() { var v data err = rows.Scan(&v.i32, &v.f32, &v.str) if err != nil { log.Fatal(err) } fmt.Printf("row[%d]: (%v, %v, %q)\n", n, v.i32, v.f32, v.str) n++ } }

Output:

row[0]: (1, 1.1, "uno")
row[1]: (2, 2.2, "dos")
row[2]: (3, 3.3, "tres")
row[3]: (4, 4.4, "quatro")

Example (Tuple)

package main import ( "database/sql" "fmt" "log" ) func main() { db, err := sql.Open("root", "../../testdata/simple.root") if err != nil { log.Fatal(err) } defer db.Close() rows, err := db.Query("SELECT (one, two, three) FROM tree") if err != nil { log.Fatal(err) } defer rows.Close() type data struct { i32 int32 f32 float32 str string } n := 0 for rows.Next() { var v data err := rows.Scan(&v.i32, &v.f32, &v.str) if err != nil { log.Fatal(err) } fmt.Printf("row[%d]: (%v, %v, %q)\n", n, v.i32, v.f32, v.str) n++ } }

Output:

row[0]: (1, 1.1, "uno")
row[1]: (2, 2.2, "dos")
row[2]: (3, 3.3, "tres")
row[3]: (4, 4.4, "quatro")

Example (WhereStmt)

package main import ( "database/sql" "fmt" "log" ) func main() { db, err := sql.Open("root", "../../testdata/simple.root") if err != nil { log.Fatal(err) } defer db.Close() rows, err := db.Query("SELECT (one, two, three) FROM tree WHERE (one>2 && two < 5)") if err != nil { log.Fatal(err) } defer rows.Close() type data struct { i32 int32 f32 float32 str string } n := 0 for rows.Next() { var v data err := rows.Scan(&v.i32, &v.f32, &v.str) if err != nil { log.Fatal(err) } fmt.Printf("row[%d]: (%v, %v, %q)\n", n, v.i32, v.f32, v.str) n++ } }

Output:

row[0]: (3, 3.3, "tres")
row[1]: (4, 4.4, "quatro")

func OpenDB

func OpenDB(file *riofs.File) *sql.DB

OpenDB opens a database/sql.DB from an already open ROOT file.

Types

This section is empty.