scan

Documentation

Index

• Variables
• func Columns(v interface{}, excluded ...string) ([]string, error)
• func ColumnsStrict(v interface{}, excluded ...string) ([]string, error)
• func Row(v interface{}, r RowsScanner) (uint32, error)
• func RowStrict(v interface{}, r RowsScanner) (uint32, error)
• func Rows(v interface{}, r RowsScanner) (uint32, error)
• func RowsStrict(v interface{}, r RowsScanner) (uint32, error)
• func Values(cols []string, v interface{}) ([]interface{}, error)
• type RowsScanner

Variables

var (
	// ErrNotAPointer is returned when a non-pointer is received
	// when a pointer is expected.
	ErrNotAPointer = errors.New("not a pointer")

	// ErrNotAStructPointer is returned when a non-struct pointer
	// is received but a struct pointer was expected
	ErrNotAStructPointer = errors.New("not a struct pointer")

	// ErrNotASlicePointer is returned when receiving an argument
	// that is expected to be a slice pointer, but it is not
	ErrNotASlicePointer = errors.New("not a slice pointer")

	// ErrStructFieldMissing is returned when trying to scan a value
	// to a column which does not match a struct. This means that
	// the struct does not have a field that matches the column
	// specified.
	ErrStructFieldMissing = errors.New("struct field missing")
)

var (
	// ErrTooManyColumns indicates that a select query returned multiple columns and
	// attempted to bind to a slice of a primitive type. For example, trying to bind
	// `select col1, col2 from mutable` to []string
	ErrTooManyColumns = errors.New("too many columns returned for primitive slice")

	// ErrSliceForRow occurs when trying to use Row on a slice
	ErrSliceForRow = errors.New("cannot scan Row into slice")

	// AutoClose is true when scan should automatically close Scanner when the scan
	// is complete. If you set it to false, then you must defer rows.Close() manually
	AutoClose = true

	// OnAutoCloseError can be used to log errors which are returned from rows.Close()
	// By default this is a NOOP function
	OnAutoCloseError = func(error) {}
)

Functions

func Columns

func Columns(v interface{}, excluded ...string) ([]string, error)

Columns scans a struct and returns a list of strings that represent the assumed column names based on the db struct tag, or the field name. Any field or struct tag that matches a string within the excluded list will be excluded from the result.

func ColumnsStrict

func ColumnsStrict(v interface{}, excluded ...string) ([]string, error)

ColumnsStrict is identical to Columns, but it only searches struct tags and excludes fields not tagged with the db struct tag.

func Row

func Row(v interface{}, r RowsScanner) (uint32, error)

Row scans a single row into a single variable. It requires that you use db.Query and not db.QueryRow, because QueryRow does not return column names. There is no performance impact in using one over the other. QueryRow only defers returning err until Scan is called, which is an unnecessary optimization for this library.

func RowStrict

func RowStrict(v interface{}, r RowsScanner) (uint32, error)

RowStrict scans a single row into a single variable. It is identical to Row, but it ignores fields that do not have a db tag

func Rows

func Rows(v interface{}, r RowsScanner) (uint32, error)

Rows scans sql rows into a slice (v)

func RowsStrict

func RowsStrict(v interface{}, r RowsScanner) (uint32, error)

RowsStrict scans sql rows into a slice (v) only using db tags

func Values

func Values(cols []string, v interface{}) ([]interface{}, error)

Values scans a struct and returns the values associated with the columns provided. Only simple value types are supported (i.e. Bool, Ints, Uints, Floats, Interface, String)

Types

type RowsScanner

type RowsScanner interface {
	Close() error
	Scan(dest ...interface{}) error
	Columns() ([]string, error)
	ColumnTypes() ([]*sql.ColumnType, error)
	Err() error
	Next() bool
}

RowsScanner is a database scanner for many rows. It is most commonly the result of *sql.DB Query(...).