在iPhone中的SQLite中插入大量数据

Question

I want to inset the 2000 Rows in database table is there any way to insert the data very Fast.currenty i am using Below code for insert the data in database.

Code :-

+(NSString* )getDatabasePath{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *writableDBPath = [documentsDirectory stringByAppendingPathComponent:@"Crocodilian"];
    return writableDBPath;

}

+(NSMutableArray *)executeQuery:(NSString*)str{

    sqlite3_stmt *statement= nil;
    sqlite3 *database;
    NSString *strPath = [self getDatabasePath];
    NSMutableArray *allDataArray = [[NSMutableArray alloc] init];
    if (sqlite3_open([strPath UTF8String],&database) == SQLITE_OK) {
        if (sqlite3_prepare_v2(database, [str UTF8String], -1, &statement, NULL) == SQLITE_OK) {


            while (sqlite3_step(statement) == SQLITE_ROW) {
                            NSInteger i = 0;
                NSInteger iColumnCount = sqlite3_column_count(statement);
                NSMutableDictionary *dict = [[NSMutableDictionary alloc] init];
                while (i< iColumnCount) {
                    NSString *str = [self encodedString:(const unsigned char*)sqlite3_column_text(statement, i)];


                NSString *strFieldName = [self encodedString:(const unsigned char*)sqlite3_column_name(statement, i)];

                    [dict setObject:str forKey:strFieldName];
                    i++;
                }

                [allDataArray addObject:dict];
                [dict release];
            }
        }

        sqlite3_finalize(statement);
    } 
    sqlite3_close(database);
    return allDataArray;
}

Thanks in Advance.

Answer 1

Your problem is, you are trying to insert one row at a time. SQLite adds commit after every insert. i had a similar issue of performance while inserting large data. I solved it using batch insert.

First create query with multiple inserts (don't need prepared statement in this case) and fire the query at once. This has major performance improvement. The only thing is that, you have to validate data before you are creating multiple insert query.

happy coding ..

Answer 2

You can try Like this for Bulk insert

My Table is Product(ProductID int,ProductName text,ShortDescription text)

sqlite3 *dtdb;
const char *dbpath=//database path

   if ((sqlite3_open(dbpath,&dtdb)==SQLITE_OK))
    {

        sqlite3_exec(dtdb, "BEGIN TRANSACTION", NULL, NULL, &errorMessage);


        char buffer[] = "INSERT INTO Product VALUES (?1, ?2, ?3)";

        sqlite3_stmt* stmt;
        sqlite3_prepare_v2(dtdb, buffer, strlen(buffer), &stmt, NULL);

        for (unsigned i = 0; i < array.count; i++)
        {
            NSDictionary *dict=[array objectAtIndex:i];

            NSArray *arKeys=[dict allKeys];


            sqlite3_bind_int(stmt,1, [[dict objectForKey:@"ProductID"]intValue]);
            sqlite3_bind_text(stmt, 2, [[NSString stringWithFormat:@"%@",[dict objectForKey:@"ProductName"]]UTF8String], -1, SQLITE_STATIC);
            sqlite3_bind_text(stmt, 3, [[NSString stringWithFormat:@"%@",[dict objectForKey:@"ShortDescription"]]UTF8String], -1, SQLITE_STATIC);


            if (sqlite3_step(stmt) != SQLITE_DONE)
            {
                printf("Commit Failed!\n");
            }

            sqlite3_reset(stmt);
        }
        if(sqlite3_exec(dtdb, "COMMIT TRANSACTION", NULL, NULL, &errorMessage)==SQLITE_OK)
        {
            NSLog(@"commited products all");
        }
        else
        {
            NSLog(@"commited  fail products all");
        }
        sqlite3_finalize(stmt);

    }

    sqlite3_close(dtdb);