如何在Sqlite中更新Blob数据类型

Question

朋友们，我想更新Blob数据字段，其中列‘是空’，每当我尝试下面的代码时，它都会产生错误，我只想知道如何更新Blob ??

        Bitmap icon = BitmapFactory.decodeResource(getResources(),R.drawable.audiobook);
        ByteArrayOutputStream stream = new ByteArrayOutputStream();
        icon.compress(Bitmap.CompressFormat.PNG,100,stream);
        simple = stream.toByteArray();
        String sql  = "UPDATE Settings SET image = "+simple+"where image IS NULL";
        db.execSQL(sql);

当我尝试这个代码时，它会生成这个错误。

java.lang.RuntimeException: Unable to start activity ComponentInfo{com.blackhat.rhythmbox/com.blackhat.rhythmbox.Welcome}: android.database.sqlite.SQLiteException: unrecognized token: ":" (code 1): , while compiling: UPDATE Settings SET image = :[B@27a97db7
 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2521)
 at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2601)
 at android.app.ActivityThread.access$800(ActivityThread.java:178)
 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1470)
 at android.os.Handler.dispatchMessage(Handler.java:111)
 at android.os.Looper.loop(Looper.java:194)
 at android.app.ActivityThread.main(ActivityThread.java:5637)
 at java.lang.reflect.Method.invoke(Native Method)
 at java.lang.reflect.Method.invoke(Method.java:372)
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:960)
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)
Caused by: android.database.sqlite.SQLiteException: unrecognized token: ":" (code 1): , while compiling: UPDATE Settings SET image = :[B@27a97db7
 at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
 at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:898)
 at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:509)
 at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
 at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
 at android.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
 at android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:1704)
 at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1635)
 at com.blackhat.rhythmbox.Welcome.addtoDatabase(Welcome.java:124)
 at com.blackhat.rhythmbox.Welcome.code(Welcome.java:67)
 at com.blackhat.rhythmbox.Welcome.onCreate(Welcome.java:57)
 at android.app.Activity.performCreate(Activity.java:6100)
 at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1112)
 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2468)
 at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2601) 
 at android.app.ActivityThread.access$800(ActivityThread.java:178) 
 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1470) 
 at android.os.Handler.dispatchMessage(Handler.java:111) 
 at android.os.Looper.loop(Looper.java:194) 
 at android.app.ActivityThread.main(ActivityThread.java:5637) 
 at java.lang.reflect.Method.invoke(Native Method) 
 at java.lang.reflect.Method.invoke(Method.java:372) 
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:960) 
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755) 

我做错了什么或者做错了什么？

Answer 1

移除：

String sql  = "UPDATE Settings SET image = "+simple+"where image IS NULL";
db.execSQL(sql);

尝试使用ContentValues.put()和SqliteDatabase.update()

ContentValues cv = new ContentValues();
cv.put("image", simple);
db.update("Settings", cv, "image is null", null);

Answer 2

在where之前添加如下空格：

String sql  = "UPDATE Settings SET image = "+simple+" where image IS NULL";