diff options
Diffstat (limited to 'src/database/sql/sql.go')
| -rw-r--r-- | src/database/sql/sql.go | 58 |
1 files changed, 32 insertions, 26 deletions
diff --git a/src/database/sql/sql.go b/src/database/sql/sql.go index 03f66c6cb7..35a74bbdb3 100644 --- a/src/database/sql/sql.go +++ b/src/database/sql/sql.go @@ -278,6 +278,27 @@ type Scanner interface { Scan(src interface{}) error } +// Out may be used to retrieve OUTPUT value parameters from stored procedures. +// +// Not all drivers and databases support OUTPUT value parameters. +// +// Example usage: +// +// var outArg string +// _, err := db.ExecContext(ctx, "ProcName", sql.Named("Arg1", Out{Dest: &outArg})) +type Out struct { + _Named_Fields_Required struct{} + + // Dest is a pointer to the value that will be set to the result of the + // stored procedure's OUTPUT parameter. + Dest interface{} + + // In is whether the parameter is an INOUT parameter. If so, the input value to the stored + // procedure is the dereferenced value of Dest's pointer, which is then replaced with + // the output value. + In bool +} + // ErrNoRows is returned by Scan when QueryRow doesn't return a // row. In such a case, QueryRow returns a placeholder *Row value that // defers this error until a Scan. @@ -1206,7 +1227,7 @@ func (db *DB) execDC(ctx context.Context, dc *driverConn, release func(error), q }() if execer, ok := dc.ci.(driver.Execer); ok { var dargs []driver.NamedValue - dargs, err = driverArgs(nil, args) + dargs, err = driverArgs(dc.ci, nil, args) if err != nil { return nil, err } @@ -1231,7 +1252,7 @@ func (db *DB) execDC(ctx context.Context, dc *driverConn, release func(error), q } ds := &driverStmt{Locker: dc, si: si} defer ds.Close() - return resultFromStatement(ctx, ds, args...) + return resultFromStatement(ctx, dc.ci, ds, args...) } // QueryContext executes a query that returns rows, typically a SELECT. @@ -1270,7 +1291,7 @@ func (db *DB) query(ctx context.Context, query string, args []interface{}, strat // The connection gets released by the releaseConn function. func (db *DB) queryDC(ctx context.Context, dc *driverConn, releaseConn func(error), query string, args []interface{}) (*Rows, error) { if queryer, ok := dc.ci.(driver.Queryer); ok { - dargs, err := driverArgs(nil, args) + dargs, err := driverArgs(dc.ci, nil, args) if err != nil { releaseConn(err) return nil, err @@ -1307,7 +1328,7 @@ func (db *DB) queryDC(ctx context.Context, dc *driverConn, releaseConn func(erro } ds := &driverStmt{Locker: dc, si: si} - rowsi, err := rowsiFromStatement(ctx, ds, args...) + rowsi, err := rowsiFromStatement(ctx, dc.ci, ds, args...) if err != nil { ds.Close() releaseConn(err) @@ -2009,7 +2030,7 @@ func (s *Stmt) ExecContext(ctx context.Context, args ...interface{}) (Result, er var res Result for i := 0; i < maxBadConnRetries; i++ { - _, releaseConn, ds, err := s.connStmt(ctx) + dc, releaseConn, ds, err := s.connStmt(ctx) if err != nil { if err == driver.ErrBadConn { continue @@ -2017,7 +2038,7 @@ func (s *Stmt) ExecContext(ctx context.Context, args ...interface{}) (Result, er return nil, err } - res, err = resultFromStatement(ctx, ds, args...) + res, err = resultFromStatement(ctx, dc.ci, ds, args...) releaseConn(err) if err != driver.ErrBadConn { return res, err @@ -2032,23 +2053,8 @@ func (s *Stmt) Exec(args ...interface{}) (Result, error) { return s.ExecContext(context.Background(), args...) } -func driverNumInput(ds *driverStmt) int { - ds.Lock() - defer ds.Unlock() // in case NumInput panics - return ds.si.NumInput() -} - -func resultFromStatement(ctx context.Context, ds *driverStmt, args ...interface{}) (Result, error) { - want := driverNumInput(ds) - - // -1 means the driver doesn't know how to count the number of - // placeholders, so we won't sanity check input here and instead let the - // driver deal with errors. - if want != -1 && len(args) != want { - return nil, fmt.Errorf("sql: expected %d arguments, got %d", want, len(args)) - } - - dargs, err := driverArgs(ds, args) +func resultFromStatement(ctx context.Context, ci driver.Conn, ds *driverStmt, args ...interface{}) (Result, error) { + dargs, err := driverArgs(ci, ds, args) if err != nil { return nil, err } @@ -2174,7 +2180,7 @@ func (s *Stmt) QueryContext(ctx context.Context, args ...interface{}) (*Rows, er return nil, err } - rowsi, err = rowsiFromStatement(ctx, ds, args...) + rowsi, err = rowsiFromStatement(ctx, dc.ci, ds, args...) if err == nil { // Note: ownership of ci passes to the *Rows, to be freed // with releaseConn. @@ -2211,7 +2217,7 @@ func (s *Stmt) Query(args ...interface{}) (*Rows, error) { return s.QueryContext(context.Background(), args...) } -func rowsiFromStatement(ctx context.Context, ds *driverStmt, args ...interface{}) (driver.Rows, error) { +func rowsiFromStatement(ctx context.Context, ci driver.Conn, ds *driverStmt, args ...interface{}) (driver.Rows, error) { var want int withLock(ds, func() { want = ds.si.NumInput() @@ -2224,7 +2230,7 @@ func rowsiFromStatement(ctx context.Context, ds *driverStmt, args ...interface{} return nil, fmt.Errorf("sql: statement expects %d inputs; got %d", want, len(args)) } - dargs, err := driverArgs(ds, args) + dargs, err := driverArgs(ci, ds, args) if err != nil { return nil, err } |