Android SQLite and Bind Variables Problem

Question

I'm trying to do a relatively simple bitwise query operation with SQLite on Android. When I use bind variables, I get no data returned when I believe should get some rows back. If I hardcode the bind variable's value directly into the SQL, it works just fine. I'm thinking I have some silly syntax issue somewhere, but I just can't see it.

So this code works just fine:

String selection = new String(FLAGS + " & 2 = 2");
cursor = db.query(TABLE_NAME, ALL_COLUMNS, selection,
    null, null, null, null, null );

This code however (using bind variables), returns no rows:

String selection = new String(FLAGS + " & ? = ?");
String[] selectionArgs = new String[]{"2", "2"};
cursor = db.query(TABLE_NAME, ALL_COLUMNS, selection,
    selectionArgs, null, null, null, null );

They both result into a syntactically identical query being built when I inspect the cursor's mQuery property through the debugger. The latter does have the mBindArgs property populated correctly as well. I'm at a loss as to how this could be failing. There are no exceptions thrown or anything, it just doesn't return any rows.

I can take the failing query, and manually swap the question marks for the two's and paste it into the ADB SQLite command line interface and it works just fine as well.

plugmind · Accepted Answer · 2010-08-23 21:41:22Z

1

If I am right the second query produces following condition:

& '2' = '2'

instead of

& 2 = 2

Try replacing & with AND

Make sure you have no ? characters in FLAG constant.

Besides what is a point of this logical condition?

answered Aug 23, 2010 at 21:41

plugmind

7,9764 gold badges36 silver badges40 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Mike Over a year ago

It's a bitwise operation, I need to use the &. I'm testing which bits of a flag value are set. I thought about the quotes too, but that would not be consistent, as far as I can tell. The mQuery property of the cursor, which shows the built SQL does not show quotes around the question marks either.

chla · Accepted Answer · 2010-10-11 09:19:45Z

1

I was facing the same problem as yours. As radek-k said, the query compares string.

One solution that may be performed is to use the following:

String selection = new String(FLAGS + " & ? = (0|?)");

answered Oct 11, 2010 at 9:19

chla

111 bronze badge

Collectives™ on Stack Overflow

Android SQLite and Bind Variables Problem

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related