Struct OptionalMetaExtractor

pub struct OptionalMetaExtractor<'a> { /* private fields */ }

Helper struct that extracts optional metadata for columns.

Implementations

impl<'a> OptionalMetaExtractor<'a>

pub fn new(iter_optional_meta: OptionalMetadataIter<'a>) -> Result<Self>

pub fn iter_signedness(&'a self) -> impl Iterator<Item = bool> + 'a

For every numeric column (in order) emits signedness data (true means unsigned).

Emits nothing if there are no signedness data in the optional metadata.

pub fn iter_charset(&'a self) -> impl Iterator<Item = Result<u16, Error>> + 'a

For every character column (in order) emits its character set.

Will use either DEFAULT_CHARSET or COLUMN_CHARSET metadata.

Warning

This iterator is infinite if DEFAULT_CHARSET is used.

Emits nothing if there are no charset data in the optional metadata.

pub fn iter_enum_and_set_charset( &'a self, ) -> impl Iterator<Item = Result<u16, Error>> + 'a

For every ENUM and SET column (in order) emits its character set.

Will use either ENUM_AND_SET_DEFAULT_CHARSET or ENUM_AND_SET_COLUMN_CHARSET metadata.

Warning

This iterator is infinite if ENUM_AND_SET_DEFAULT_CHARSET is used.

Emits nothing if there are no charset data in the optional metadata.

pub fn iter_primary_key( &'a self, ) -> Peekable<impl Iterator<Item = Result<u64>> + 'a>

Iterates over column indexes for columns that are primary keys.

Returns peekable iterator so that it is possible to observe next PK index.

Emits nothing if there are no PK data in the optinal metadata.

pub fn iter_column_name( &'a self, ) -> impl Iterator<Item = Result<ColumnName<'a>>> + 'a

For every column (in order) emits its name

Emits nothing if there are no column name data in the optional metadata.