1 files changed, 56 insertions, 7 deletions
diff --git a/ext/session/sqlite3session.h b/ext/session/sqlite3session.h
index 1ea90dce4..0c9e78607 100644
--- a/ext/session/sqlite3session.h
+++ b/ext/session/sqlite3session.h
@@ -885,6 +885,18 @@ int sqlite3changeset_concat(
 
 
 /*
+** CAPI3REF: Upgrade the Schema of a Changeset/Patchset
+*/
+int sqlite3changeset_upgrade(
+  sqlite3 *db,
+  const char *zDb,
+  int nIn, const void *pIn,       /* Input changeset */
+  int *pnOut, void **ppOut        /* OUT: Inverse of input */
+);
+
+
+
+/*
 ** CAPI3REF: Changegroup Handle
 **
 ** A changegroup is an object used to combine two or more 
@@ -931,6 +943,38 @@ typedef struct sqlite3_changegroup sqlite3_changegroup;
 int sqlite3changegroup_new(sqlite3_changegroup **pp);
 
 /*
+** CAPI3REF: Add a Schema to a Changegroup
+** METHOD: sqlite3_changegroup_schema
+**
+** This method may be used to optionally enforce the rule that the changesets
+** added to the changegroup handle must match the schema of database zDb
+** ("main", "temp", or the name of an attached database). If
+** sqlite3changegroup_add() is called to add a changeset that is not compatible
+** with the configured schema, SQLITE_SCHEMA is returned and the changegroup
+** object is left in an undefined state.
+**
+** A changeset schema is considered compatible with the database schema in
+** the same way as for sqlite3changeset_apply(). Specifically, for each
+** table in the changeset, there exists a database table with:
+**
+** <ul>
+**   <li> The name identified by the changeset, and
+**   <li> at least as many columns as recorded in the changeset, and
+**   <li> the primary key columns in the same position as recorded in 
+**        the changeset.
+** </ul>
+**
+** The output of the changegroup object always has the same schema as the
+** database nominated using this function. In cases where changesets passed
+** to sqlite3changegroup_add() have fewer columns than the corresponding table
+** in the database schema, these are filled in using the default column
+** values from the database schema. This makes it possible to combined 
+** changesets that have different numbers of columns for a single table
+** within a changegroup, provided that they are otherwise compatible.
+*/
+int sqlite3changegroup_schema(sqlite3_changegroup*, sqlite3*, const char *zDb);
+
+/*
 ** CAPI3REF: Add A Changeset To A Changegroup
 ** METHOD: sqlite3_changegroup
 **
@@ -998,13 +1042,18 @@ int sqlite3changegroup_new(sqlite3_changegroup **pp);
 ** If the new changeset contains changes to a table that is already present
 ** in the changegroup, then the number of columns and the position of the
 ** primary key columns for the table must be consistent. If this is not the
-** case, this function fails with SQLITE_SCHEMA. If the input changeset
-** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is
-** returned. Or, if an out-of-memory condition occurs during processing, this
-** function returns SQLITE_NOMEM. In all cases, if an error occurs the state
-** of the final contents of the changegroup is undefined.
-**
-** If no error occurs, SQLITE_OK is returned.
+** case, this function fails with SQLITE_SCHEMA. Except, if the changegroup
+** object has been configured with a database schema using the
+** sqlite3changegroup_schema() API, then it is possible to combine changesets
+** with different numbers of columns for a single table, provided that
+** they are otherwise compatible.
+**
+** If the input changeset appears to be corrupt and the corruption is
+** detected, SQLITE_CORRUPT is returned. Or, if an out-of-memory condition
+** occurs during processing, this function returns SQLITE_NOMEM. 
+**
+** In all cases, if an error occurs the state of the final contents of the
+** changegroup is undefined. If no error occurs, SQLITE_OK is returned.
 */
 int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);