從sqlite數據庫中的表中刪除所有記錄

Question

我知道這是一個非常常見的問題，我嘗試了我在這裏找到的所有東西。但問題仍然存在。

現在的問題是我試圖刪除3個表中的所有記錄與下面的代碼，但他們沒有被刪除

const char *dbpath = [dbPathString UTF8String]; 
sqlite3 *sqliteDB; 

if (sqlite3_open(dbpath, &sqliteDB) == SQLITE_OK) 
{ 
    //Delete all records from attempts 
    sqlite3_stmt *statement; 

    NSString *deleteSQL = [NSString stringWithFormat: @"DELETE FROM table1"]; 

    const char *delete_stmt = [deleteSQL UTF8String]; 
    sqlite3_prepare_v2(sqliteDB, delete_stmt, -1, &statement, NULL); 

    sqlite3_finalize(statement); 
    sqlite3_close(sqliteDB); 
} 
if (sqlite3_open(dbpath, &sqliteDB) == SQLITE_OK) 
{ 
    //Delete all records from attempts 
    sqlite3_stmt *statement; 

    NSString *deleteSQL = [NSString stringWithFormat: @"DELETE FROM table2"]; 

    const char *delete_stmt = [deleteSQL UTF8String]; 
    sqlite3_prepare_v2(sqliteDB, delete_stmt, -1, &statement, NULL); 

    sqlite3_finalize(statement); 
    sqlite3_close(sqliteDB); 
} 
if (sqlite3_open(dbpath, &sqliteDB) == SQLITE_OK) 
{ 
    //Delete all records from attempts 
    sqlite3_stmt *statement; 

    NSString *deleteSQL = [NSString stringWithFormat: @"DELETE FROM table"]; 

    const char *delete_stmt = [deleteSQL UTF8String]; 
    sqlite3_prepare_v2(sqliteDB, delete_stmt, -1, &statement, NULL); 

    sqlite3_finalize(statement); 
    sqlite3_close(sqliteDB); 
} 

我試圖與如果條件一樣

if (sqlite3_prepare_v2(sqliteDB, delete_stmt, -1, &statement, NULL) == SQLITE_OK) { 
    NSLog("All records deleted"); 
} 

這如果條件得到執行，我有控制檯日誌中的聲明。 我使用的是Xcode 5.0。 請幫幫我。 Thanx提前

Answer 1

sqlite3_prepare_v2只是準備聲明。 要實際執行它，您還必須致電sqlite3_step。

Answer 2

親愛的朋友，這是有點複雜的編碼嘗試使用外部類，方便編碼

這個鏈接將幫助您

How to insert update delete in database operation and also save database in document directory

進行刪除記錄，您可以使用

NSString *strDelete = [Database executeScalarQuery:@"DELETE FROM table1"]; 

快樂編碼！