Interface Rows

Close closes the [Rows], preventing further enumeration. If [Rows.Next] is called and returns false and there are no further result sets, the [Rows] are closed automatically and it will suffice to check the result of [Rows.Err]. Close is idempotent and does not affect the result of [Rows.Err].

ColumnTypes returns column information such as column type, length, and nullable. Some information may not be available from some drivers.

Columns returns the column names. Columns returns an error if the rows are closed.

Err returns the error, if any, that was encountered during iteration. Err may be called after an explicit or implicit [Rows.Close].

Next prepares the next result row for reading with the [Rows.Scan] method. It returns true on success, or false if there is no next result row or an error happened while preparing it. [Rows.Err] should be consulted to distinguish between the two cases.

Every call to [Rows.Scan], even the first one, must be preceded by a call to [Rows.Next].

NextResultSet prepares the next result set for reading. It reports whether there is further result sets, or false if there is no further result set or if there is an error advancing to it. The [Rows.Err] method should be consulted to distinguish between the two cases.

After calling NextResultSet, the [Rows.Next] method should always be called before scanning. If there are further result sets they may not have rows in the result set.

Scan copies the columns in the current row into the values pointed at by dest. The number of values in dest must be the same as the number of columns in [Rows].

Scan converts columns read from the database into the following common Go types and special types provided by the sql package:

 *string
 *[]byte
 *int, *int8, *int16, *int32, *int64
 *uint, *uint8, *uint16, *uint32, *uint64
 *bool
 *float32, *float64
 *interface{}
 *RawBytes
 *Rows (cursor value)
 any type implementing Scanner (see Scanner docs)
Copy

In the most simple case, if the type of the value from the source column is an integer, bool or string type T and dest is of type *T, Scan simply assigns the value through the pointer.

Scan also converts between string and numeric types, as long as no information would be lost. While Scan stringifies all numbers scanned from numeric database columns into *string, scans into numeric types are checked for overflow. For example, a float64 with value 300 or a string with value "300" can scan into a uint16, but not into a uint8, though float64(255) or "255" can scan into a uint8. One exception is that scans of some float64 numbers to strings may lose information when stringifying. In general, scan floating point columns into *float64.

If a dest argument has type *[]byte, Scan saves in that argument a copy of the corresponding data. The copy is owned by the caller and can be modified and held indefinitely. The copy can be avoided by using an argument of type [*RawBytes] instead; see the documentation for [RawBytes] for restrictions on its use.

If an argument has type *interface{}, Scan copies the value provided by the underlying driver without conversion. When scanning from a source value of type []byte to *interface{}, a copy of the slice is made and the caller owns the result.

Source values of type [time.Time] may be scanned into values of type *time.Time, *interface{}, *string, or *[]byte. When converting to the latter two, [time.RFC3339Nano] is used.

Source values of type bool may be scanned into types *bool, *interface{}, *string, *[]byte, or [*RawBytes].

For scanning into *bool, the source may be true, false, 1, 0, or string inputs parseable by [strconv.ParseBool].

Scan can also convert a cursor returned from a query, such as "select cursor(select * from my_table) from dual", into a [*Rows] value that can itself be scanned from. The parent select query will close any cursor [*Rows] if the parent [*Rows] is closed.

If any of the first arguments implementing [Scanner] returns an error, that error will be wrapped in the returned error.