SQLiteException: Unrecognized token when reading from database

问题

I've created an SQLite database inside application, populated it and now I'm trying to read from it. The app keeps crashing and this is the logcat I receive:

12-30 05:53:18.008: E/AndroidRuntime(6205): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.testparsing/com.example.testparsing.Urnik}: android.database.sqlite.SQLiteException: unrecognized token: "4c" (code 1): , while compiling: SELECT predmet FROM predmeti WHERE dan=PONEDELJEK and ura=2 and oddelek=4c

Function for reading from database:

Cursor getSubject(String dan, int ura, String oddelek){
    String[] columnNames = new String[1];
    columnNames[0] = SQLiteHelper.PREDMET;
    String selection = SQLiteHelper.DAN+"="+dan+" and "+SQLiteHelper.URA+"="+ura+" and "+SQLiteHelper.ODDELEK+"="+oddelek;
    open();
    return db.query(
            SQLiteHelper.IME_TABELE, 
            columnNames, 
            selection, 
            null, null, null, null);
}

How I'm trying to read:

TextView tw1p = (TextView) findViewById(R.id.tview1p);
DatabaseHandler db = new DatabaseHandler(getApplicationContext());

Cursor c = db.getSubject("PONEDELJEK", 2, "4c");
String predmet = c.getString(c.getColumnIndex(SQLiteHelper.PREDMET));
tw1p.setText(predmet);

A screenshot of table, just to prove that oddelek "4c" in fact does exist:

回答1:

SELECT predmet FROM predmeti WHERE dan=PONEDELJEK and ura=2 and oddelek=4c

You need to quote your string literals, for example:

SELECT predmet FROM predmeti WHERE dan='PONEDELJEK' and ura=2 and oddelek='4c'

But it's better to use ? placeholder for literals:

SELECT predmet FROM predmeti WHERE dan=? and ura=? and oddelek=?

and change your null selectionArgs to

new String[] { dan, Integer.toString(ura), oddelek }

回答2:

String selection = SQLiteHelper.DAN+"="+dan+" and "+SQLiteHelper.URA+"="+ura+" and "+SQLiteHelper.ODDELEK+"='"+oddelek+"'";

Replace with this and check

回答3:

issue is due to missing quotes only :-

Example

 db.delete(TABLE_NA,E, ADDRESS + "= '" + address + "'", null);

Please check below field + "= '" + address + "'"

{Issue as address is string so it should be under 'address' }

来源：https://stackoverflow.com/questions/20838233/sqliteexception-unrecognized-token-when-reading-from-database

标签

android

sqlite

android-sqlite