Class TDbKeyCol

class TDbKeyCol;

Description

Defines a key column in an index.

The data members are public as this is really a structure to group the attributes of the key column together. Two non-default constructors are provided for convenience.

Members

Defined in TDbKeyCol:
EAsc, EDesc, TDbKeyCol(), TDbKeyCol(), TDbKeyCol(), TOrder, iLength, iName, iOrder

inline TDbKeyCol();

Description

Constructs an uninitialised object. Default constructor. It is necessary because there are also non-default constructors in this class.

IMPORT_C TDbKeyCol(const TDesC &aName, TOrder anOrder=EAsc);

Description

Parameters

const TDesC &aName TOrder anOrder

IMPORT_C TDbKeyCol(const TDesC &aName, TInt aLength, TOrder anOrder=EAsc);

Description

Constructs an object with the given name, ordering and optional truncation length.

Parameters

const TDesC &aName The column name. TInt aLength If present, this specifies a limit on how many characters of a Text or LongText column are used for the key. This should only be used for the last key column in an index. It is required for keys on LongText columns. TOrder anOrder The ordering for the key column. By default this is ascending order.

TOrder

Description

Specifies whether a key column in an index should be sorted in ascending or descending order.

EAsc Use ascending order. EDesc Use descending order.

TOrder iOrder;

Description

The ordering of the key.

TInt iLength;

Description

The maximum number of characters used to index Text or LongText columns. If equal to KDbUndefinedLength (the default), all the characters in the defined column will be used.

TDbColNameC iName;

Description

The column name for the key.