CODEWITHSUNDEEP
javasqliteandroid-studioandroid-sqlite
Aljohn Dela CRUZ
Aljohn Dela CRUZ

Reputation: 123

Retrieving a single column or two columns in android studio from sqlite

public class DatabaseHelper extends SQLiteOpenHelper {
    public static final String DATABASE_NAME = "Student.db";
    public static final String TABLE_NAME = "student_table";
    public static final String COL_1 = "ID";
    public static final String COL_2 = "NAME";
    public static final String COL_3 = "SURNAME";
    public static final String COL_4 = "MARKS";
    public static final String COL_5 = "DATETIMEZ";

public Cursor NAME_MARKS() {
        SQLiteDatabase db = this.getWritableDatabase();
Cursor res = db.rawQuery("select * from " + TABLE_NAME, null);

//does not work 

Cursor res = db.rawQuery("select COL_2,COL_3 from " + TABLE_NAME, null);{}

Upvotes: 0

Views: 839

Answers (1)

Mureinik
Mureinik

Reputation: 311028

col_2 and col_3 are the names of the variables, not the columns in the database. If you want to use them, you'll need to use some sort of string manipulation/concatination. E.g.:

Cursor res = 
    db.rawQuery("select " + COL_2 + ", " + COL_3 + " from " + TABLE_NAME, null);

Upvotes: 1

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