Session Module C Interface
Generate A Patchset From A Session Object
int sqlite3session_patchset( sqlite3_session *pSession, /* Session object */ int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */ void **ppPatchset /* OUT: Buffer containing patchset */ );
The differences between a patchset and a changeset are that:
- DELETE records consist of the primary key fields only. The original values of other fields are omitted.
- The original values of any modified fields are omitted from UPDATE records.
A patchset blob may be used with up to date versions of all sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, attempting to use a patchset blob with old versions of the sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
Because the non-primary key "old.*" fields are omitted, no SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset is passed to the sqlite3changeset_apply() API. Other conflict types work in the same way as for changesets.
Changes within a patchset are ordered in the same way as for changesets generated by the sqlite3session_changeset() function (i.e. all changes for a single table are grouped together, tables appear in the order in which they were attached to the session object).