CODEWITHSUNDEEP
javaandroidsqlite
user3244162
user3244162

Reputation: 101

Android SQLlite database search method

I have a problem with Android sqlite and cursor, I want to verify that the value entered in a text box is not in my database.

ContenuBDD contenuBdd = new ContenuBDD(MainActivity.this);
                contenuBdd.open();


                if(contenuBdd.recherche(text.getText().toString())== true)
                {
                    System.out.println("ok");
                }
                else
                {
                    System.out.println("not ok");

                }

                contenuBdd.close();

code of search method :

public boolean recherche(String titre){

    Cursor c = bdd.query(TABLE_CONTENU, new String[] {COL_ID, COL_VALEUR}, COL_VALEUR + " LIKE \"" + titre +"\"", null, null, null, null);
    if(c == null)
    {
        return true;
    }
    else
    {
        return false;
    }
}

For now, even if I enter a value that is not in the database, "not ok" is displayed

my request :

String query = new String( "select valeur from table_contenu where valeur = "+titre);

my logcat :

02-12 10:51:02.338: E/AndroidRuntime(11642): android.database.sqlite.SQLiteException: near "=": syntax error (code 1): , while compiling: select valeur from table_contenu where valeur =

Upvotes: 0

Views: 130

Answers (4)

EpicPandaForce
EpicPandaForce

Reputation: 81539

As I mentioned in my answer at https://stackoverflow.com/a/24144236/2413303

The way you're supposed to do a query is the following:

private String[] allColumns = { Table1.COLUMN_ID, Table1.COLUMN_NAME,
        Table1.COLUMN_OTHERCOLUMN };

public ItemDB findEmployeeById(long id)
{
    ItemDB employee = null;
    Cursor cursor = database.query(ItemTable.TABLE_NAME, allColumns, ItemTable.COLUMN_ID + " = ?", new String[] {""+id}, null, null, null);
    if(cursor.moveToFirst())
    {
        employee = createItemFromCursor(cursor);
    }
    return employee;
}

Another possible way is using rawQuery if you need to specifically rename a column (for example, the id to _id because the adapters demand it):

public Cursor getRawQueryCursor()
{
    return database
            .rawQuery(
                    "SELECT id as _id, name, dateFrom || ' - ' || dateTo as date FROM " + ItemTable.TABLE_NAME + " WHERE lower(name) = ?",
                    new String[] { inputName });
}

Upvotes: 1

Zar E Ahmer
Zar E Ahmer

Reputation: 34360

public boolean CheckIsDataAlreadyInDBorNot(String TableName, String dbfield, String fieldValue)
    { 
         db = this.getReadableDatabase();

        String Query = "Select * from " + TableName + " where " + dbfield + "="
                + fieldValue;
        Cursor cursor = db.rawQuery(Query, null);

        if(cursor.getCount() <=0)
         {
             return false;
         }
             return true;
    }

Upvotes: -1

David N
David N

Reputation: 519

You should prefer to test :

 if(c.getCount() == 0)

instead of 

  if(c == null)

And maybe your could manage it with a raw query like :

String q = "SELECT * FROM your_table WHERE titre = titre";
Cursor c= mDb.rawQuery(q, null);

Upvotes: 1

Smutje
Smutje

Reputation: 18123

I assume, SQLite always returns a Cursor, but in case of nothing found, Cursor#getCount() will result in 0, as displayed in the API.

Upvotes: 0

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