android - Trouble Parsing XML Into SQLite Database -
the application working on parses data .xml file , stores database. however, upon each application launch, database grow in size number of table rows parsed data stored into. example, if parsed data took 3 rows store, each subsequent application launch increase database size of (in terms of rows) six, nine, twelve, , on , forth.
what prevent table increasing in size upon each application launch. have tried resetting database each time, i'm not sure how correctly go or if solution should going for.
i have view display database in entirety:
public class qaview extends activity { @override protected void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.qa_view); textview tv = (textview) findviewbyid(r.id.tvdata); qadatabase entries = new qadatabase(this); try { entries.open(); string data = entries.getalldata(); tv.settext(data); entries.close(); } catch(sqlexception e) { e.printstacktrace(); } } } i have parser code processes data .xml file:
xmlresourceparser parser = getresources().getxml(r.xml.qa); try { while(parser.next() != xmlpullparser.end_document) { if(parser.geteventtype() != xmlpullparser.start_tag) { continue; } string name = parser.getname(); if(name.equals("question")) { question = readtextquestion(parser); } else if(name.equals("options")) { readtextanswers(parser); } } } catch(xmlpullparserexception e) { e.printstacktrace(); } catch(ioexception e) { e.printstacktrace(); } i have corresponding database code:
public class qadatabase { public static final string key_rowid = "_id"; public static final string key_question = "question"; public static final string key_answer1 = "answer1"; public static final string key_answer2 = "answer2"; public static final string key_answer3 = "answer3"; public static final string key_answer4 = "answer4"; public static final string key_answer5 = "answer5"; public static final string key_correct = "correct"; public static final string database_name = "questionanswerdatabase"; public static final string database_table = "questionanswertable"; public static final int database_version = 2; private databasehelper ourhelper; private final context ourcontext; private sqlitedatabase ourdatabase; private static class databasehelper extends sqliteopenhelper { private databasehelper(context context) { super(context, database_name, null, database_version); } @override public void oncreate(sqlitedatabase sqlitedatabase) { sqlitedatabase.execsql("create table " + database_table + " (" + key_rowid + " integer primary key, " + key_question + " text not null, " + key_answer1 + " text not null, " + key_answer2 + " text not null, " + key_answer3 + " text not null, " + key_answer4 + " text not null, " + key_answer5 + " text not null, " + key_correct + " text not null);" ); } @override public void onupgrade(sqlitedatabase sqlitedatabase, int i, int i2) { sqlitedatabase.execsql("drop table if exists " + database_table); oncreate(sqlitedatabase); } } public qadatabase(context c) { ourcontext = c; } public qadatabase open() throws sqlexception { ourhelper = new databasehelper(ourcontext); ourdatabase = ourhelper.getwritabledatabase(); return this; } public void close() { ourhelper.close(); } public void createentry(string question, string answer1, string answer2, string answer3, string answer4, string answer5, string correct) { contentvalues cv = new contentvalues(); cv.put(key_question, question); cv.put(key_answer1, answer1); cv.put(key_answer2, answer2); cv.put(key_answer3, answer3); cv.put(key_answer4, answer4); cv.put(key_answer5, answer5); cv.put(key_correct, correct); ourdatabase.insert(database_table, null, cv); } public string getalldata() { string[] columns = new string[] {key_rowid, key_question, key_answer1, key_answer2, key_answer3, key_answer4, key_answer5, key_correct}; cursor c = ourdatabase.query(database_table, columns, null, null, null, null, null); string result = ""; while(c.movetonext()) { result = result + c.getstring(0) + " " + c.getstring(1) + " " + c.getstring(2) + " " + c.getstring(3) + " " + c.getstring(4) + " " + c.getstring(5) + " " + c.getstring(6) + " " + c.getstring(7) + "\n"; } return result; } public string getquestion(long l) throws sqlexception { string[] columns = new string[] {key_rowid, key_question, key_answer1, key_answer2, key_answer3, key_answer4, key_answer5, key_correct}; cursor c = ourdatabase.query(database_table, columns, key_rowid + "=" + l, null, null, null, null); if(c != null) { // move cursor first row c.movetofirst(); // id "l" in "questions" column string question = c.getstring(1); return question; } // otherwise, return null return null; } public string getanswerchoice(long l, int answerchoicenumber) throws sqlexception { string[] columns = new string[] {key_rowid, key_question, key_answer1, key_answer2, key_answer3, key_answer4, key_answer5, key_correct}; cursor c = ourdatabase.query(database_table, columns, key_rowid + "=" + l, null, null, null, null); if(c != null) { // move cursor first row c.movetofirst(); // id "l" in "answers" column string correctanswer = c.getstring(answerchoicenumber + 2); // need offset 2 key_rowid , key_question columns return correctanswer; } // otherwise, return null return null; } public cursor getalltitles() { return ourdatabase.query(database_table, new string[] { key_rowid, key_answer1, key_answer2, key_answer3, key_answer4, key_answer5, key_correct}, null, null, null, null, null); }
you can assign fixed primary id (rowid) each question, doing again , again gives duplicate primary key constraint exception, table wouldn't grow.
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