diff options
Diffstat (limited to 'select.go')
| -rw-r--r-- | select.go | 31 |
1 files changed, 12 insertions, 19 deletions
@@ -79,16 +79,16 @@ func (s Store[R]) SelectWhere(db Handle, partialQuery string, args ...any) (resu return result, nil } -func startSelectQuery(db Handle, plan internal.Plan, query string, args ...any) (rows *sql.Rows, indexes [][]int, err error) { - rows, err = db.Query(query, args...) +func startSelectQuery(db Handle, plan internal.Plan, query string, args ...any) (returnedRows *sql.Rows, indexes [][]int, returnedError error) { + rows, err := db.Query(query, args...) if err != nil { return nil, nil, fmt.Errorf("during Query(): %w", err) } defer func() { - if err != nil { - closeErr := rows.Close() + if returnedError != nil { + closeErr := rows.Close() // NOTE: Not `returnedRows.Close()`! We may have `rows != nil && returnedRows == nil`. if closeErr != nil { - err = fmt.Errorf("%w (additional error during rows.Close(): %s)", err, closeErr.Error()) + returnedError = fmt.Errorf("%w (additional error during rows.Close(): %s)", returnedError, closeErr.Error()) } } }() @@ -103,8 +103,8 @@ func startSelectQuery(db Handle, plan internal.Plan, query string, args ...any) indexes[idx], ok = plan.IndexByColumnName[columnName] if !ok { return nil, nil, fmt.Errorf( - "result has column %q in position %d, but no field in record type has `db:%[1]q`", - columnName, idx, + "result has column %q in position %d, but no field in type %s has `db:%[1]q`", + columnName, idx, plan.TypeName, ) } } @@ -125,11 +125,7 @@ func collectRow(rows *sql.Rows, v reflect.Value, slots []any, indexes [][]int) e for idx, index := range indexes { slots[idx] = v.FieldByIndex(index).Addr().Interface() } - err := rows.Scan(slots...) - if err != nil { - return fmt.Errorf("during rows.Scan(): %w", err) - } - return nil + return rows.Scan(slots...) } func mergeCloseError(typeName string, err, closeErr error) error { @@ -147,7 +143,6 @@ func mergeCloseError(typeName string, err, closeErr error) error { // according to the column names reported by the database as part of the result set. // // If there are no rows in the result set, [sql.ErrNoRows] is returned. -// If there are multiple rows in the result set, [ErrMultipleRows] is returned. // // Warning: Because of limitations in the interface of database/sql, this function is built on [Store.Select] and cannot be any faster than it. // For maximum performance, use [Store.SelectOneWhere] which avoids the overhead of potentially having to read multiple rows. @@ -158,13 +153,10 @@ func (s Store[R]) SelectOne(db Handle, query string, args ...any) (result R, err var results []R results, err = s.Select(db, query, args...) if err == nil { - switch len(results) { - case 0: + if len(results) == 0 { err = sql.ErrNoRows - case 1: + } else { result = results[0] - default: - err = ErrMultipleRows } } return @@ -173,7 +165,8 @@ func (s Store[R]) SelectOne(db Handle, query string, args ...any) (result R, err // SelectOneWhere is like [Store.SelectOne], but you only provide the part of the SELECT query that comes after the WHERE. // See [Store.SelectWhere] for an explanation of how the full query is constructed from this partial query. // -// This method is significantly more efficient than [Store.SelectWhere] and using it is recommended when possible. +// This method is significantly more efficient than [Store.SelectOne]. +// Prefer using it instaed of [Store.SelectOne] whenever possible. func (s Store[R]) SelectOneWhere(db Handle, partialQuery string, args ...any) (result R, err error) { // NOTE: This function body should be as short as possible to reduce the binary size after monomorphization. // Any expression that does not depend on type R should be factored out into a reusable function. |