"Database is locked" in delete operation in my sqlite - iphone

Question

I have a function like this for delete table row in my apps, but I have an error that said "database is locked".
- (BOOL) deleteByCaption:(NSString *)registerCaption
{
const char *dbpath = [databasePath UTF8String];
if (sqlite3_open(dbpath, &database) == SQLITE_OK) {
NSString *querySQL = [NSString stringWithFormat:#"DELETE FROM tabelA WHERE CONTENT_CAPTION = \"%#\"", registerCaption];
const char *query_stmt = [querySQL UTF8String];
// NSMutableArray *resultArray = [[NSMutableArray alloc] init];
if(sqlite3_prepare_v2(database, query_stmt, -1, &statement, NULL) == SQLITE_OK){
if(sqlite3_step(statement) == SQLITE_ROW){
return YES;
}else{
NSLog(#"Error while creating delete statement. '%s'", sqlite3_errmsg(database));
return NO;
}
}
sqlite3_reset(statement);
}
return NO;
}

Answer 1

You are missing sqlite3_finalize(). Look at //PUT HERE part in following code.
- (BOOL) deleteByCaption:(NSString *)registerCaption
{
BOOL isDeleted = NO; //EDIT
const char *dbpath = [databasePath UTF8String];
if (sqlite3_open(dbpath, &database) == SQLITE_OK) {
NSString *querySQL = [NSString stringWithFormat:#"DELETE FROM tabelA WHERE CONTENT_CAPTION = \"%#\"", registerCaption];
const char *query_stmt = [querySQL UTF8String];
// NSMutableArray *resultArray = [[NSMutableArray alloc] init];
if(sqlite3_prepare_v2(database, query_stmt, -1, &statement, NULL) == SQLITE_OK){
if(sqlite3_step(statement) == SQLITE_ROW){
isDeleted = YES;
//return YES; //EDIT
}else{
NSLog(#"Error while creating delete statement. '%s'", sqlite3_errmsg(database));
//return NO; //EDIT
}
}
sqlite3_reset(statement);
sqlite3_finalize(statement); //PUT HERE
sqlite3_close(database); //EDIT
}
//return NO; //EDIT
return isDeleted; //EDIT
}
EDIT:
Try to set one variable to return.
Look at the edited portion in above code. Search for //EDIT.

Answer 2

In deleteByCaption function too, You are returning from function without closing data base.
You should write following statements before writing "RETURN YES" or "RETURN NO"
sqlite3_finalize(statement);
sqlite3_close(database);
Please check all functions where your have used sqlite3_open() function.
and make sure to write sqlite3_close() function before returning from that function.