and modify some functions to return const pointers. Add const qualifiers
to local variable declarations or casts to remove the const qualifier
in those places where write access is needed.
in the clustered index to be smaller than the indexed prefix in secondary
indexes.
row_ext_lookup(): Return NULL if the column is not stored externally.
trx_undo_rec_get_partial_row(): row_build(): Add parameter row_ext_t** ext.
row_build_index_entry(): Add the parameter row_ext_t* ext.
Invoke row_ext_lookup() to fetch prefixes of externally stored columns.
upd_node_t, undo_node_t, purge_node_t: Add the field row_ext_t* ext.
BLOB pointers, trx_id, and roll_ptr.
btr_empty(), btr_create(), page_create(): Add parameter "index", as some
index information will be encoded on the compressed page.
Define REC_NODE_PTR_SIZE as 4.
Allow btr_page_reorganize() and btr_page_reorganize_low() to fail.
Define the error code DB_ZIP_OVERFLOW.
Make row_ins_index_entry_low() static.
page0zip: Encode the index, log reorganized records, and store uncompressed
fields separately from the compressed data stream.
