데이터베이스에 삽입 할 때 이러한 테이블 예외가 발생하지 않습니다.

Question

간단한 대기 품질 제어 응용 프로그램에서 작업하고 있습니다. SQLite를 사용하여 대기 질 측정 값을 저장해야합니다. SQLiteOpenHelper 클래스를 확장 한 db 헬퍼 클래스를 만들었습니다. 단일 테이블 measurements을 작성해야합니다.

public class SmogDbHelper extends SQLiteOpenHelper { 

    private static final int DATABASE_VERSION = 1; 

    public static final String DATABASE_NAME = "smog.db"; 

    interface Tables { 
     String MEASUREMENT = "measurement"; 
    } 

    interface Triggers { 
     String ON_MEASUREMENT_INSERTED = "on_measurement_inserted"; 
    } 

    public SmogDbHelper(Context context){ 
     super(context, DATABASE_NAME, null, DATABASE_VERSION); 
    } 

    @Override 
    public void onCreate(SQLiteDatabase db) { 

     final String SQL_CREATE_TABLE_MEASUREMENT = 
       "CREATE TABLE " + Tables.MEASUREMENT + " (" + MeasurementEntry._ID + 
       " INTEGER PRIMARY KEY, " + 
       MeasurementEntry.COLUMN_LONGITUDE + " REAL NOT NULL, " + 
       MeasurementEntry.COLUMN_LATITUDE + " REAL NOT NULL, " + 
       MeasurementEntry.COLUMN_FROM_DATE_TIME + " INTEGER NOT NULL, " + 
       MeasurementEntry.COLUMN_TILL_DATE_TIME + " INTEGER, " + 
       MeasurementEntry.COLUMN_PM_1 + " REAL NOT NULL, " + 
       MeasurementEntry.COLUMN_PM_25 + " REAL NOT NULL, " + 
       MeasurementEntry.COLUMN_PM_10 + " REAL NOT NULL, " + 
       MeasurementEntry.COLUMN_POLUTION_LEVEL + " INTEGER NOT NULL, " + 
       MeasurementEntry.COLUMN_AIR_QUALITY_INDEX + " REAL NOT NULL, " + 
       MeasurementEntry.COLUMN_SOURCE + " TEXT NOT NULL" + 
       ");"; 

     final String SQL_CREATE_ON_MEASUREMENT_INSERTED_TRIGGER = "CREATE TRIGGER " + Triggers.ON_MEASUREMENT_INSERTED + 
       " AFTER INSERT ON " + Tables.MEASUREMENT + 
       " BEGIN " + 
       "DELETE FROM LOG WHERE " + MeasurementEntry.COLUMN_FROM_DATE_TIME + " < " + 
       "(strftime('%s', 'now') - 604800);\n" + 
       " END;"; 

     db.execSQL(SQL_CREATE_TABLE_MEASUREMENT); 
     db.execSQL(SQL_CREATE_ON_MEASUREMENT_INSERTED_TRIGGER); 
    } 

    @Override 
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { 
     db.execSQL("DROP TABLE IF EXISTS " + Tables.MEASUREMENT); 
     db.execSQL("DROP TRIGGER IF EXISTS " + Triggers.ON_MEASUREMENT_INSERTED); 
    } 
} 

그리고 다음 단위 테스트를 사용하여 테스트하십시오.

@RunWith(AndroidJUnit4.class) 
@LargeTest 
public class TestDb { 

    private static final String LOG_TAG = "TestDb"; 
    private SmogDbHelper smogDbHelper; 
    private SQLiteDatabase db; 

    // remove old database if present before starting tests 
    @Before 
    public void setUp() throws Exception { 
     getTargetContext().deleteDatabase(SmogDbHelper.DATABASE_NAME); 
     smogDbHelper = new SmogDbHelper(getTargetContext()); 
     db = smogDbHelper.getWritableDatabase(); 
    } 

    @After 
    public void tearDown() throws Exception { 
     db.close(); 
    } 

    @Test 
    public void testTableCreation() { 

     Assert.assertEquals(true, db.isOpen()); 

     // hash set of all tables we are looking for in the db 
     final HashSet<String> tableNameHashSet = new HashSet<String>(); 
     tableNameHashSet.add(SmogContract.MeasurementEntry.TABLE_NAME); 

     Cursor c = db.rawQuery("SELECT name FROM sqlite_master WHERE type ='table'", null); 

     Assert.assertTrue("Error: This means that the database has not been created correctly", 
       c.moveToFirst()); 

     // remove all table names from hash map which are in db. 
     do { 
      String tableName = c.getString(0); 
      Log.v(LOG_TAG, tableName); 
      tableNameHashSet.remove(tableName); 
     } while (c.moveToNext()); 

     c.close(); 
     // if this fails not all tables have been created correctly 
     Assert.assertTrue("Error: Your database is missing " + tableNameHashSet.size() 
       + " tables.", tableNameHashSet.isEmpty()); 

     c = db.rawQuery("PRAGMA table_info(" + SmogContract.MeasurementEntry.TABLE_NAME + ")", 
       null); 

     Assert.assertTrue("Error: Unable to query the database for table information.", 
       c.moveToFirst()); 

     // all columns we want to look for in MeasurementEntry 
     final HashSet<String> measurementColumnHashSet = new HashSet<String>(); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry._ID); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry.COLUMN_AIR_QUALITY_INDEX); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry.COLUMN_FROM_DATE_TIME); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry.COLUMN_TILL_DATE_TIME); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry.COLUMN_LATITUDE); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry.COLUMN_LONGITUDE); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry.COLUMN_PM_1); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry.COLUMN_PM_25); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry.COLUMN_PM_10); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry.COLUMN_SOURCE); 
     measurementColumnHashSet.add(SmogContract.MeasurementEntry.COLUMN_POLUTION_LEVEL); 

     int columnNameIndex = c.getColumnIndex("name"); 
     do { 
      String columnName = c.getString(columnNameIndex); 
      Log.v(LOG_TAG, columnName); 
      measurementColumnHashSet.remove(columnName); 
     } while (c.moveToNext()); 

     Assert.assertTrue("Error: The database doesn't contain all of the required location entry columns", 
       measurementColumnHashSet.isEmpty()); 

     c.close(); 
    } 

    @Test 
    public void testMeasurementTable() { 

     ContentValues measurementValues = TestUtilities.createMeasurementValues(); 
     long measurementRowId = db.insert(SmogContract.MeasurementEntry.TABLE_NAME, 
       null, measurementValues); 
     Assert.assertTrue(measurementRowId != -1); 

     Cursor measurementCursor = db.query(
       SmogContract.MeasurementEntry.TABLE_NAME, 
       null, null, null, null, null, null 
     ); 
     Assert.assertTrue("Error: No Records returned from location query", 
       measurementCursor.moveToFirst()); 

     measurementCursor.close(); 
    } 

} 

삽입 및 쿼리 테스트를 실행할 때 테이블 생성 테스트가 제대로 작동하지만 다음 예외가 발생합니다.

android.database.sqlite.SQLiteException: no such table: main.LOG (code 1): , while compiling: INSERT INTO measurement(pm_25,from_date_time,pm_10,polution_level,source,till_date_time,air_quality_index,longitude,latitude,pm_1) VALUES (?,?,?,?,?,?,?,?,?,?) 

나는이 문제의 원인에 관한 아이디어가 없습니다. 어떤 도움이나 제안도 늘 그렇듯이 크게 감사합니다.

DELETE FROM LOG ... 

을하지만 그런 테이블이 없습니다 :

Answer 1

트리거는 말한다.

아마도 같은 테이블에서 삭제하고 싶었을 것입니다.