未创建外键语法错误表

Question

由于FOREIGN KEY语法错误，我的表没有被创建，但我似乎无法弄清楚。我确定在调用FK之前先创建int。下面是与FK

public class PlayerStatsDatabase { 
public static final String KEY_ROWID = "_id"; 
public static final String PLAYER_ID = "PlayerId"; 
public static final String KEY_SCORE = "Goals_Scored"; 
public static final String KEY_MINUTES = "Minutes_Played"; 
public static final String KEY_SUBIN = "Substitute_In"; 
public static final String KEY_SUBOUT = "Substitute_Out"; 
public static final String KEY_BOOKING = "Booked"; 

private static final String TAG = "PlayersStatsDatabase"; 
private DatabaseHelper mDbHelper; 
private SQLiteDatabase mDb; 

private static final String DATABASE_NAME = "Players"; 
private static final String SQLITE_TABLE = "PlayerStats"; 
private static final int DATABASE_VERSION = 2; 

private final Context mCtx; 

private static final String DATABASE_CREATE = 
    "CREATE TABLE if not exists " + SQLITE_TABLE + " (" + 
    KEY_ROWID + " integer PRIMARY KEY autoincrement," + 
    PLAYER_ID + "integer"+" FOREIGN KEY ("+PLAYER_ID+") REFERENCES "+DATABASE_NAME+" ("+KEY_ROWID+"),"+ 
    KEY_SCORE + "," + 
    KEY_MINUTES + "," + 
    KEY_SUBIN + "," + 
    KEY_SUBOUT + "," + 
    KEY_BOOKING + ")" ; 

主键为我的班德代码在这个类

public class PlayerDbAdapter { 

private static final String DATABASE_TABLE = "Players"; 
private static final String DATABASE_CREATE = "CREATE TABLE "+DATABASE_TABLE+" (_id integer primary key autoincrement, Player_Name text not null, Player_Position text not null, Player_Number text not null, Team text not null);"; 
private static final int DATABASE_VERSION =1; 
    public static final String KEY_BODY = "Player_Name"; 
    public static final String KEY_ROWID = "_id"; 
    public static final String KEY_TITLE = "Player_Position"; 
    public static final String KEY_NUMBER = "Player_Number"; 
    public static final String KEY_TEAM = "Team"; 
private static final String TAG = "PlayerDbAdapter"; 
    private final Context mCtx; 
    private SQLiteDatabase mDb; 
    private DatabaseHelper mDbHelper; 

    public PlayerDbAdapter(Context paramContext) 
    { 
    this.mCtx = paramContext; 
    } 

    public void close() 
    { 
    this.mDbHelper.close(); 
    } 


    public long createPlayers(String playerName, String playerPosition, String playerNumber, String team) 
    { 
    ContentValues localContentValues = new ContentValues(); 
    localContentValues.put(KEY_BODY, playerName); 
    localContentValues.put(KEY_TITLE, playerPosition); 
    localContentValues.put(KEY_NUMBER, playerNumber); 
    localContentValues.put(KEY_TEAM, team); 
    try{ 
     return this.mDb.insert("Players", null, localContentValues); 
    } catch (Exception e) { 
     Log.e("Juma", e.getMessage()); 
    } 

    return 0; 
    } 

logcat的

04-18 19:28:08.544: E/Database(352): Failure 1 (near "FOREIGN": syntax error) on 0x2b5840 when preparing 'CREATE TABLE if not exists PlayerStats (_id integer PRIMARY KEY autoincrement,PlayerIdinteger FOREIGN KEY (PlayerId) REFERENCES Players (_id),Goals_Scored,Minutes_Played,Substitute_In,Substitute_Out,Booked)'.

是不是因为我不是插入Player_id oNCreate方法？

Answer 1

这是修改的例子，我从SQLite documentation了：

CREATE TABLE track(
    KEY_ROWID INTEGER PRIMARY KEY autoincrement, 
    PLAYER_ID INTEGER, 
    KEY_SCORE TEXT, 
    FOREIGN KEY(PLAYER_ID) REFERENCES anotherTable(THE_KEY_ROWID_HERE), 
    FOREIGN KEY(KEY_ROWID, PLAYER_ID) 
      REFERENCES yetAnotherTable(THE_KEY_ROWID_THERE, THE_PLAYER_ID_THERE) 
); 

正如你所看到的，你必须添加外键后所有列定义 - 不要试图把他们内列定义。你可以有多个，也可以有组合列的外键。

最后是精心打造的SQL字符串时，你的发言：

CREATE TABLE if not exists PlayerStats (
_id  integer PRIMARY KEY autoincrement, 
    PlayerId integer, 
    Goals_Scored, 
    Minutes_Played, 
    ... 

...缺少类型的某些列。

p.s.：这一个应该工作，例如

private static final String TABLE_CREATE = 
    "CREATE TABLE if not exists " + TABLE_NAME + " (" + 
    KEY_ROWID  + " integer PRIMARY KEY autoincrement," 
    ANOTHER_COLUMN + " text" +")"; 

private static final String SQLITE_CREATE = 
    "CREATE TABLE if not exists " + SQLITE_TABLE + " (" + 
    KEY_ROWID + " integer PRIMARY KEY autoincrement," + 
    PLAYER_ID + " integer," 
    KEY_SCORE + " text," + 
    KEY_MINUTES + " text," + 
    KEY_SUBIN + " text," + 
    KEY_SUBOUT + " text," + 
    KEY_BOOKING + " text," 
    +" FOREIGN KEY("+PLAYER_ID+") REFERENCES "+TABLE_NAME+" ("+KEY_ROWID+"))"; 

希望我可以帮助一下。

干杯！

Answer 2

您必须在android sqlite中将主键的名称作为_id。

Answer 3

根据日志，你必须靠近“洋”，语法错误的清楚，有没有除了整数逗号后的“PlayerId”和“整数”，之间的空间。此外，您没有提交[Goals_Scored，Minutes_Played，Substitute_In，Substitute_Out，Booked]的类型。

我建议学习更多关于SQL查询的知识，您可以先在桌面上使用sqlite。