I created an SQLite database, which has a table in it. The database and table can be viewed in SQlite Browser, but when I fire queries, after adding the database to assets folder, it recognizes the database but fails to find the table and gives 'no such table' error.
I am using constructor and calling onCreate() method in constructor; as the 'database open helper inherited class' which I have named as 'FetchRecords' class is not an activity.
What could be wrong with the code? Sharing the code;
1- FetchRecords class :
package com.example.piechartgenerationfromdatabase;
import android.app.Activity;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
public class FetchRecords extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 3;
private static final String DATABASE_NAME = "AlarmDataSqliteFinal";
private static final String TABLE_NAME = "AlarmDataTable";
Cursor cursor = null;
Cursor cursor1 = null;
SQLiteDatabase db = null;
String[] distinctAlarmNames;
String[] allValuesInColumnAlarmNames;
int[] occurancesOfDistinctAlarmNames;
String[] topFiveAlarmNames;
int[] temp;
int totalNumberOfValuesInAlarmNamesColumn;
public FetchRecords(Context context) {
super(context, "AlarmDataSqliteFinal", null, DATABASE_VERSION);
onCreate(this.getReadableDatabase());
}
public String[] getTopFiveAlarmNames(){
return this.topFiveAlarmNames;
}
public String[] getDistinctAlarmNames(){
return this.distinctAlarmNames;
}
public int[] getOccurancesOfDistinctAlarmNames(){
return this.occurancesOfDistinctAlarmNames;
}
@Override
public void onCreate(SQLiteDatabase db){
//creating queries
String numberOfRowsInDatabaseCalculatingQuery = "SELECT * FROM AlarmDataTable";
String distinctQuery = "SELECT DISTINCT AlarmName FROM AlarmDataTable";
//getting permission to read database
db = this.getReadableDatabase();
System.out.println(db.toString());
//Firing queries
cursor = db.rawQuery(distinctQuery, null); //Here I get the exception
int numberOfDistinctRecords = cursor.getCount();
//instantiating arrays
distinctAlarmNames = new String[numberOfDistinctRecords];
allValuesInColumnAlarmNames = new String[totalNumberOfValuesInAlarmNamesColumn];
occurancesOfDistinctAlarmNames = new int[numberOfDistinctRecords];
//inserting values in arrays
int indexOfDistinctNamesArray = 0;
int indexOfAllValuesInColumnAlarmNamesArray = 0;
while(cursor.moveToNext()){
distinctAlarmNames[indexOfDistinctNamesArray] = cursor.getString(cursor.getColumnIndex("AlarmNames"));
indexOfDistinctNamesArray++;
}
cursor.close();
cursor1 = db.rawQuery(numberOfRowsInDatabaseCalculatingQuery,null);
totalNumberOfValuesInAlarmNamesColumn = cursor1.getCount();
while(cursor1.moveToNext()){
allValuesInColumnAlarmNames[indexOfAllValuesInColumnAlarmNamesArray] = cursor.getString(cursor.getColumnIndex("AlarmNames"));
indexOfAllValuesInColumnAlarmNamesArray++;
}
cursor1.close();
//calculating top five alarms and their ocuurences
int occurenceVariable = 0;
int indexOfOccurenceArray=0;
for(int i=0; i<numberOfDistinctRecords;i++) {
for (int j = 0; j < totalNumberOfValuesInAlarmNamesColumn; j++) {
if (distinctAlarmNames[i].equalsIgnoreCase(allValuesInColumnAlarmNames[j])) {
occurenceVariable++;
}
}
occurancesOfDistinctAlarmNames[indexOfOccurenceArray] = occurenceVariable;
occurenceVariable = 0;
indexOfOccurenceArray++;
}
temp = new int[occurancesOfDistinctAlarmNames.length];
for(int i=0; i<occurancesOfDistinctAlarmNames.length;i++){
temp[i] = occurancesOfDistinctAlarmNames[i];
}
//calculating top five largest occurences
int topFiveOccurances[] = new int[5];
int largest = 0;
for(int unsortedIndex=1; unsortedIndex<5;unsortedIndex++){
for(int sortedIndex=0; sortedIndex<unsortedIndex; sortedIndex++){
if(occurancesOfDistinctAlarmNames[unsortedIndex] > occurancesOfDistinctAlarmNames[sortedIndex]){
int temp = occurancesOfDistinctAlarmNames[sortedIndex];
occurancesOfDistinctAlarmNames[sortedIndex] = occurancesOfDistinctAlarmNames[unsortedIndex];
occurancesOfDistinctAlarmNames[unsortedIndex] = temp;
}
}
}
for(int i=0; i<5;i++){
topFiveOccurances[i] = occurancesOfDistinctAlarmNames[i];
}
int alarmnamestopfiveindex = 0;
for(int i=0; i<occurancesOfDistinctAlarmNames.length;i++){
for(int j=0; j<5;j++){
if(temp[i] == topFiveOccurances[j]){
topFiveAlarmNames[alarmnamestopfiveindex] = distinctAlarmNames[i];
alarmnamestopfiveindex++;
}
}
}
System.out.println("temp length"+temp.length);
//System.out.println("");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
2- Activity that calls the FetchRecords class :
package com.example.piechartgenerationfromdatabase;
import android.content.Intent;
import android.os.Bundle;
import androidx.appcompat.app.AppCompatActivity;
public class PieChartActivity extends AppCompatActivity {
PieChartView pieChart;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//fetching records
//Intent fetchRecords = new Intent(PieChartActivity.this,FetchRecords.class);
//startActivity(fetchRecords);
FetchRecords fetch = new FetchRecords(this.getApplicationContext());
pieChart = new PieChartView(this,fetch.getTopFiveAlarmNames(),fetch.temp);
setContentView(pieChart);
}
}
