Using the LIMIT statement in a SQLite query

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栀梦
栀梦 2020-11-27 16:38

I have a query that selects rows in a ListView without having a limit. But now that I have implemented a SharedPreferences that the user can select

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  • 2020-11-27 16:56

    The equals (=) operator is not used with the LIMIT clause. Remove it.

    Here's an example LIMIT query:

    SELECT column FROM table ORDER BY somethingelse LIMIT 5, 10
    

    Or:

    SELECT column FROM table ORDER BY somethingelse LIMIT 10
    

    In your case, the correct statement would be:

    return wDb.query(TABELANOME, new String[] {IDTIT, TAREFATIT, SUMARIOTIT}, CONCLUIDOTIT + "=1", null, null, null, null, String.valueOf(limite));
    

    Take a look here at the SQLite select syntax: http://www.sqlite.org/syntaxdiagrams.html#select-stmt

    This image is rather useful: http://www.sqlite.org/images/syntax/select-stmt.gif

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  • 2020-11-27 16:59

    Due to this bug which also doesn't allow for negative limits

    8,-1

    I had to use this workaround

    SQLiteQueryBuilder builder = new SQLiteQueryBuilder();
    builder.setTables(table);
    String query = builder.buildQuery(projection, selection, null, null, null, sortOrder, null);
    query+=" LIMIT 8,-1";
    
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  • 2020-11-27 17:06

    For anyone stumbling across this answer looking for a way to use a LIMIT clause with an OFFSET, I found out from this bug that Android uses the following regex to parse the limit clause of a query:

    From <framework/base/core/java/android/database/sqlite/SQLiteQueryBuilder.java>

    LIMIT clause is checked with following sLimitPattern.

    private static final Pattern sLimitPattern = Pattern.compile("\\s*\\d+\\s*(,\\s*\\d+\\s*)?");
    

    Note that the regex does accept the format offsetNumber,limitNumber even though it doesn't accept the OFFSET statement directly.

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