The JET_COLUMNID data type identifies a column within a table.
typedef unsigned long JET_COLUMNID;
Identifies a column within a table.
Column IDs are unique within a single table. Once a column is known to have a certain column ID, it will always have that column ID. Restore from backup will not change the value of a column ID. However, if one or more table columns, prior to a specific table column, are deleted, a compact database can then change the value of a column ID.
In some cases, column IDs are the only means of identifying columns. When a temporary table is created, its columns do not have names, but an array of column IDs is returned by the create function.
Columns in different tables can have the same column ID.
Requires Windows Vista, Windows XP, or Windows 2000 Professional.
Requires Windows Server 2008, Windows Server 2003, or Windows 2000 Server.
Declared in Esent.h.