How to compress (or cleanup) Sqlite database after delete?

Question

Is there a way to compress (or cleanup) a Sqlite database after a large number of rows have been deleted?
For example, if I have a database file around 1Mb and delete all the rows the database file remains at 1Mb (despite being empty). If I then open this file in Sqlite Administrator and click on "CleanUp" the size goes down to 4kb.
Is this functionality available from inside my app?
Thanks

Answer 1

I'm finally getting some time to look at this but not doing too well.
Running the following code gives the below error message:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *path = [documentsDirectory stringByAppendingPathComponent:@"myDB.sql"];
int success;
if (sqlite3_open([path UTF8String], &database) == SQLITE_OK) {
// My first delete statement
// My second delete statement
// My third delete statement
// VACUUM STATEMENT
const char *sql4 = "VACUUM";
sqlite3_stmt *statement4;
if (sqlite3preparev2(database, sql4, -1, &statement4, NULL) != SQLITE_OK) {
NSAssert1(0, @"Error: failed to prepare vacuum with message '%s'.", sqlite3_errmsg(database));
success = sqlite3_step(statement4);
sqlite3_reset(statement4);
if (success != SQLITE_DONE) {
NSAssert1(0, @"Error: failed to execute vacuum with message '%s'.", sqlite3_errmsg(database));
sqlite3_finalize(statement4);
sqlite3_close(database);
error:
Error: failed to execute vacuum with message 'unable to open database file'.
I know the database file is open ok because the rows are being deleted fine. The problem is just cleaning up the database file with the VACUUM command.
Has anyone successfully run this statement on the iPhone?