table

type ColDesc struct {
	Field        string
	Type         string
	Collation    string
	Null         string
	Key          string
	DefaultValue interface{}
	Extra        string
	Privileges   string
	Comment      string
}

type Column struct {
	*model.ColumnInfo
	// If this column is a generated column, the expression will be stored here.
	GeneratedExpr ast.ExprNode
}

type Index interface {
	// Meta returns IndexInfo.
	Meta() *model.IndexInfo
	// Create supports insert into statement.
	Create(ctx sessionctx.Context, rm kv.RetrieverMutator, indexedValues []types.Datum, h int64) (int64, error)
	// Delete supports delete from statement.
	Delete(sc *stmtctx.StatementContext, m kv.Mutator, indexedValues []types.Datum, h int64) error
	// Drop supports drop table, drop index statements.
	Drop(rm kv.RetrieverMutator) error
	// Exist supports check index exists or not.
	Exist(sc *stmtctx.StatementContext, rm kv.RetrieverMutator, indexedValues []types.Datum, h int64) (bool, int64, error)
	// GenIndexKey generates an index key.
	GenIndexKey(sc *stmtctx.StatementContext, indexedValues []types.Datum, h int64, buf []byte) (key []byte, distinct bool, err error)
	// Seek supports where clause.
	Seek(sc *stmtctx.StatementContext, r kv.Retriever, indexedValues []types.Datum) (iter IndexIterator, hit bool, err error)
	// SeekFirst supports aggregate min and ascend order by.
	SeekFirst(r kv.Retriever) (iter IndexIterator, err error)
	// FetchValues fetched index column values in a row.
	// Param columns is a reused buffer, if it is not nil, FetchValues will fill the index values in it,
	// and return the buffer, if it is nil, FetchValues will allocate the buffer instead.
	FetchValues(row []types.Datum, columns []types.Datum) ([]types.Datum, error)
}

type IndexIterator interface {
	Next() (k []types.Datum, h int64, err error)
	Close()
}

type RecordIterFunc func(h int64, rec []types.Datum, cols []*Column) (more bool, err error)

type Slice []Table

type Table interface {
	// IterRecords iterates records in the table and calls fn.
	IterRecords(ctx sessionctx.Context, startKey kv.Key, cols []*Column, fn RecordIterFunc) error

	// RowWithCols returns a row that contains the given cols.
	RowWithCols(ctx sessionctx.Context, h int64, cols []*Column) ([]types.Datum, error)

	// Row returns a row for all columns.
	Row(ctx sessionctx.Context, h int64) ([]types.Datum, error)

	// Cols returns the columns of the table which is used in select.
	Cols() []*Column

	// WritableCols returns columns of the table in writable states.
	// Writable states includes Public, WriteOnly, WriteOnlyReorganization.
	WritableCols() []*Column

	// Indices returns the indices of the table.
	Indices() []Index

	// WritableIndices returns write-only and public indices of the table.
	WritableIndices() []Index

	// DeletableIndices returns delete-only, write-only and public indices of the table.
	DeletableIndices() []Index

	// RecordPrefix returns the record key prefix.
	RecordPrefix() kv.Key

	// IndexPrefix returns the index key prefix.
	IndexPrefix() kv.Key

	// FirstKey returns the first key.
	FirstKey() kv.Key

	// RecordKey returns the key in KV storage for the row.
	RecordKey(h int64) kv.Key

	// AddRecord inserts a row which should contain only public columns
	// skipHandleCheck indicates that recordID in r has been checked as not duplicate already.
	AddRecord(ctx sessionctx.Context, r []types.Datum, skipHandleCheck bool) (recordID int64, err error)

	// UpdateRecord updates a row which should contain only writable columns.
	UpdateRecord(ctx sessionctx.Context, h int64, currData, newData []types.Datum, touched []bool) error

	// RemoveRecord removes a row in the table.
	RemoveRecord(ctx sessionctx.Context, h int64, r []types.Datum) error

	// AllocAutoID allocates an auto_increment ID for a new row.
	AllocAutoID(ctx sessionctx.Context) (int64, error)

	// Allocator returns Allocator.
	Allocator(ctx sessionctx.Context) autoid.Allocator

	// RebaseAutoID rebases the auto_increment ID base.
	// If allocIDs is true, it will allocate some IDs and save to the cache.
	// If allocIDs is false, it will not allocate IDs.
	RebaseAutoID(ctx sessionctx.Context, newBase int64, allocIDs bool) error

	// Meta returns TableInfo.
	Meta() *model.TableInfo

	// Seek returns the handle greater or equal to h.
	Seek(ctx sessionctx.Context, h int64) (handle int64, found bool, err error)

	// Type returns the type of table
	Type() Type
}

type Type int16