Databases
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    <ol> <li>You're closing your database when returning cursors -- thus the cursor will point to a closed database which means you can't use it (you might be able to use the first record since you moved to that before closing it). Not to mention opening/closing takes up some time. You should just open the DB once in <code>onCreate</code> and then close it once in <code>onDestroy</code>.</li> <li>Android only supports a single SQL statement in <code>rawQuery</code>, so what you want cannot be achieved by nesting SQL statements</li> </ol> <p>Try something like:</p> <pre><code>String sql = "SELECT CityType.rowid, Location.locationName FROM Location, CityType " + "WHERE Location.cityId = CityType.rowid " + "AND CityType.cityName = " + saa; </code></pre> <p>Also please post the error output from LogCat.</p> <p>Change your DatabaseHelper to something like the following (notice I'm not opening the database for each query - you need to make sure to call the <code>open</code> and <code>close</code> methods in the <code>onCreate</code> and <code>onDestroy</code> methods of your Activity).</p> <pre><code>public class DataBaseHelper extends SQLiteOpenHelper { ... private SQLiteDatabase mDb; // change openDatabase to this: // call it ONCE in onCreate of your activity public SQLiteDatabase open() throws SQLException { if (mDb != null) return; // already opened mDb = this.getReadableDatabase(); return mDb; } // call this in the onDestroy of your activity public void close() { if (mDb == null) return; // db is not open mDb.close(); mDb = null; } // Change getLoc and your other methods to be something like this public Cursor getLocation() { if (mDb == null) throw new NullPointerException("Database has not been opened by activity"); String saa = cabbookingapplication.Selection; String sql = "SELECT CityType.rowid, Location.locationName FROM Location, CityType " + "WHERE Location.cityId = CityType.rowid " + "AND CityType.cityName = " + saa; return mDb.rawQuery(sql); } ... } </code></pre> <p>Also</p> <ul> <li>Make sure to call <code>startManagingCursor</code> on any cursors you don't close pretty much straight away to avoid memory leaks (i.e. cursors you use in adapters should be managed)</li> <li>I haven't called <code>Cursor.moveToFirst()</code> in my above example, so call that if you want. </li> </ul> <p>I usually call it outside of my adapter to so I can do something like</p> <pre><code>if (cursor.getCount() &gt; 0) { // we have at least 1 record while (cursor.moveToNext()) { // do something with current row } } else { // no rows, show an empty message or something } </code></pre>
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    1. POERROR/AndroidRuntime: Caused by: android.database.sqlite.SQLiteException: no such column: Gurgaon:
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    1. USJoseph Earl
    1. USJoseph Earl
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    1. POERROR/AndroidRuntime: Caused by: android.database.sqlite.SQLiteException: no such column: Gurgaon:
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    1. VO
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    1. CO@ joseph /data/data/cabs.h/databases/CabBookingDatabase.sqlite SQLiteDatabase created and never closed
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    2. COearl hi...it works but problem is in place of "saa" variable "null" is coming
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    3. COAdded code at the bottom of my post to explain using an adapter and not opening the database every time. `saa` comes from `cabbookingapplication.Selection` so `Selection` must be null - I don't have to the code for your booking app so I can't say why that is null.
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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