samedi 7 mars 2015

Error when query Empty SQLite DB

I am writing an Android App and I have a DB Helper class to do just about anything that is related to a SQLite DB. Name of the class is "ResultsDbAdapter". Following are some info about the DB:



private static final String DATABASE_NAME = "PROJECT_RESULTS";
private static final String DATABASE_TABLE = "projectResults";
private static final int DATABASE_VERSION = 1;

//Fields(Columns) for Database
public static final String[] PROJECT_RESULTS_FIELDS = new String[] {
KEY_ROWID,
"title",
"interval",
"start",
"end",
"duration",
"totalHits",
"itemKeys",
"keyHits"
};


In the ResultsDbAdapter class is a method to query the DB for a specific entry by searching the "title" column.



public Cursor fetchByTitle(String pTitle) throws SQLException {
Cursor mCursor = mDb.query(DATABASE_TABLE, PROJECT_RESULTS_FIELDS, "title" + "=" + pTitle, null,
null, null, null, null);
return mCursor;
}


The "fetchByTitle" method is then called in the Main Activity with the following snippet of code:



final ResultsDbAdapter db = new ResultsDbAdapter (this);
db.open(); //Open and Close methods are also written in the "ResultsDbAdapter" class
final Cursor cursor = db.fetchByTitle(mTitle); //mTitle is the title of the record needed
if (cursor.moveToFirst()){
// do something
} else {
//do something else
}
db.close();


The app when first run on an emulator causes an error which I think is because there are no entries. So there is no cursor to return causing the error. Following is the error from logcat:



03-07 21:53:51.230: E/SQLiteLog(1158): (1) near "Title": syntax error
03-07 21:53:51.310: E/AndroidRuntime(1158): FATAL EXCEPTION: main
03-07 21:53:51.310: E/AndroidRuntime(1158): Process: com.jevans.surveybud, PID: 1158
03-07 21:53:51.310: E/AndroidRuntime(1158): android.database.sqlite.SQLiteException: near "Title": syntax error (code 1): , while compiling: SELECT _id, title, interval, start, end, duration, totalHits, itemKeys, keyHits FROM projectResults WHERE title=My Title
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:889)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:500)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:37)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:44)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1314)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1161)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1032)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1238)
03-07 21:53:51.310: E/AndroidRuntime(1158): at com.jevans.surveybud.ResultsDbAdapter.fetchByTitle(ResultsDbAdapter.java:141)
03-07 21:53:51.310: E/AndroidRuntime(1158): at com.jevans.surveybud.ResultsActivity.saveDb(ResultsActivity.java:163)
03-07 21:53:51.310: E/AndroidRuntime(1158): at com.jevans.surveybud.ResultsActivity$1.onClick(ResultsActivity.java:138)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.view.View.performClick(View.java:4438)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.view.View$PerformClick.run(View.java:18422)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.os.Handler.handleCallback(Handler.java:733)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.os.Handler.dispatchMessage(Handler.java:95)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.os.Looper.loop(Looper.java:136)
03-07 21:53:51.310: E/AndroidRuntime(1158): at android.app.ActivityThread.main(ActivityThread.java:5017)
03-07 21:53:51.310: E/AndroidRuntime(1158): at java.lang.reflect.Method.invokeNative(Native Method)
03-07 21:53:51.310: E/AndroidRuntime(1158): at java.lang.reflect.Method.invoke(Method.java:515)
03-07 21:53:51.310: E/AndroidRuntime(1158): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
03-07 21:53:51.310: E/AndroidRuntime(1158): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
03-07 21:53:51.310: E/AndroidRuntime(1158): at dalvik.system.NativeStart.main(Native Method)


I apologize for the seemingly fundamental question as I am a newbie with Android programming. However, I have been stuck at this for a very long time. Can someone please help to resolve this error?


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