Implementation of append mode concurrent insert operations in tables in a page-based concurrent relational database management system is carried out by defining a set of last pages as a current cache into which rows may be inserted by appenders. Append mode insert operations for each page in the current cache are serialized. Appenders seek to access the pages in the current cache using a two-pass process in which latches are sought to be acquired conditionally in the first pass and unconditionally in the second pass. A shared data structure is provided to define a current cache and a next cache for a table supporting append mode inserts in the relational database. The shared data structure includes information reflecting the unused space for each page in the current cache.