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SQL Android Query formulation with multiple conditions

I am writing an android application that is trying to pull data from a database based on two separate criteria.

The fields of workout and exercise are both strings in the database. I want to return a cursor with only those rows that satisfy BOTH criteria. Oh and I would also like it to be sorted in date order...

public Cursor graphQuery(String exercise, String work开发者_如何学Goout) {
     Cursor cursor = mDb.query(DATABASE_TABLE, new String [] {KEY_DATE, KEY_REPS,       
         KEY_REPS_FEEL, KEY_WEIGHT, KEY_WEIGHT_FEEL}, "KEY_WORKOUT=" + workout + "AND" +  
         "KEY_EXERCISE=" + exercise, null , null, null, KEY_DATE); 

     return cursor;
}

I am a new android coder and would appreciate the help!


Use selection and selectionArgs:

public Cursor graphQuery(String exercise, String workout) {
     Cursor cursor = mDb.query(DATABASE_TABLE, new String [] {KEY_DATE, KEY_REPS,       
         KEY_REPS_FEEL, KEY_WEIGHT, KEY_WEIGHT_FEEL}, "KEY_WORKOUT = ? AND KEY_EXERCISE = ?",
         new String[] { workout, exercise },
         null,
         null,
         KEY_DATE); 

     return cursor;
}

Notice how the selection String has ?s inplace of actual values and the actual values are passed in as a String[] and in the selectionArgs paramter. SQLite will replace those ?s with the values from the String[] selectionArgs.


Short answer: There are spaces missing around "AND" --> " AND ".:

Long answer: Please use parameter markers - you will see missing spaces immediately then:

Cursor cursor = mDb.query(DATABASE_TABLE, new String [] { KEY_DATE, KEY_REPS,       
         KEY_REPS_FEEL, KEY_WEIGHT, KEY_WEIGHT_FEEL }, "KEY_WORKOUT=? and KEY_EXERCISE=?", new String[] { workout, exercise }, null, null, KEY_DATE);
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