android.database.DatabaseUtils#longForQuery ( )源码实例Demo

int calculateDebugTableInsertionPoint() {
    SQLiteDatabase db = mDeDatabase.getReadableDatabase();
    String queryCountDebugDbRows = "SELECT COUNT(*) FROM " + TABLE_DEBUG;
    int size = (int) DatabaseUtils.longForQuery(db, queryCountDebugDbRows, null);
    if (size < MAX_DEBUG_DB_SIZE) {
        return size;
    }

    // This query finds the smallest timestamp value (and if 2 records have
    // same timestamp, the choose the lower id).
    queryCountDebugDbRows = "SELECT " + DEBUG_TABLE_KEY +
            " FROM " + TABLE_DEBUG +
            " ORDER BY "  + DEBUG_TABLE_TIMESTAMP + "," + DEBUG_TABLE_KEY +
            " LIMIT 1";
    return (int) DatabaseUtils.longForQuery(db, queryCountDebugDbRows, null);
}
 

public static long getChangeCount(String tableName)
{
    String selection = getSelectionForSync();
    MapContentProviderHelper map = (MapContentProviderHelper) MapBase.getInstance();
    SQLiteDatabase db = map.getDatabase(true);

    try {
        // From sources of DatabaseUtils.queryNumEntries()
        String s = (!TextUtils.isEmpty(selection)) ? " where " + selection : "";
        return DatabaseUtils.longForQuery(db, "select count(*) from " + tableName + s, null);
    } catch (SQLiteException e) {
        e.printStackTrace();
        Log.d(TAG, e.getLocalizedMessage());
        return 0;
    }
}
 

long findAccountLastAuthenticatedTime(Account account) {
    SQLiteDatabase db = mDeDatabase.getReadableDatabase();
    return DatabaseUtils.longForQuery(db,
            "SELECT " + AccountsDb.ACCOUNTS_LAST_AUTHENTICATE_TIME_EPOCH_MILLIS
                    + " FROM " + TABLE_ACCOUNTS + " WHERE " + ACCOUNTS_NAME + "=? AND "
                    + ACCOUNTS_TYPE + "=?",
            new String[] {account.name, account.type});
}
 

/**
 * Sets the maximum size the database will grow to. The maximum size cannot
 * be set below the current size.
 *
 * @param numBytes the maximum database size, in bytes
 * @return the new maximum database size
 */
public long setMaximumSize(long numBytes) {
    long pageSize = getPageSize();
    long numPages = numBytes / pageSize;
    // If numBytes isn't a multiple of pageSize, bump up a page
    if ((numBytes % pageSize) != 0) {
        numPages++;
    }
    long newPageCount = DatabaseUtils.longForQuery(this, "PRAGMA max_page_count = " + numPages,
            null);
    return newPageCount * pageSize;
}
 

public long countForQuery(String query, String[] selectionArgs) {
  if (StringUtil.isEmpty(query)) {
    return 0l;
  }
  SQLiteDatabase db = dbHelper.getReadableDatabase();
  return DatabaseUtils.longForQuery(db, query, selectionArgs);
}
 

public int getBookCategoryId(int bookId) {

        return (int) DatabaseUtils.longForQuery(getReadableDatabase(),
                " SELECT " +
                        BooksInformationDBContract.BooksCategories.COLUMN_NAME_CATEGORY_ID +
                        " FROM " +
                        BooksInformationDBContract.BooksCategories.TABLE_NAME +
                        " WHERE " +
                        BooksInformationDBContract.BooksCategories.COLUMN_NAME_BOOK_ID + "=?",
                new String[]{String.valueOf(bookId)}
        );

    }
 

public long getBookIdByDownloadId(long enquId) {
    return DatabaseUtils.longForQuery(getReadableDatabase(),
            SQL.SELECT +
                    BooksInformationDBContract.StoredBooks.COLUMN_NAME_BookID +
                    SQL.FROM +
                    BooksInformationDBContract.StoredBooks.TABLE_NAME +
                    SQL.WHERE +
                    BooksInformationDBContract.StoredBooks.COLUMN_NAME_ENQID + "=?",
            new String[]{Long.toString(enquId)}
    );
}
 

public boolean isDownloadEnqueue(long enqueueId) {
    return 1L == DatabaseUtils.longForQuery(getReadableDatabase(),
            " SELECT COUNT(*)" +
                    " FROM " +
                    BooksInformationDBContract.StoredBooks.TABLE_NAME +
                    " WHERE " +
                    BooksInformationDBContract.StoredBooks.COLUMN_NAME_ENQID + "=?",
            new String[]{String.valueOf(enqueueId)}
    );


}
 

/**
 * @param titleId  the title id to return its positin
 * @param parentId
 * @return the o based position of this title within is parent
 */
public int getTitlePositionUnderParent(int titleId, int parentId) {
    return (int) DatabaseUtils.longForQuery(getReadableDatabase(),
            SQL.SELECT + "count(*)" + SQL.FROM +
                    "(" + SQL.SELECT + " null " + SQL.FROM + BookDatabaseContract.TitlesEntry.TABLE_NAME +
                    SQL.WHERE +
                    BookDatabaseContract.TitlesEntry.COLUMN_NAME_PARENT_ID + "=? and " +
                    BookDatabaseContract.TitlesEntry.COLUMN_NAME_ID + "<? )",
            new String[]{String.valueOf(parentId), String.valueOf(titleId)});
}
 

public boolean isPartPageCombinationValid(int partNumber, int pageNumber) {
    return DatabaseUtils.longForQuery(getReadableDatabase(),
            SQL.SELECT + " count(*) " + SQL.FROM +
                    "(" + SQL.SELECT + SQL.NULL + SQL.FROM + BookDatabaseContract.PageEntry.TABLE_NAME
                    + SQL.WHERE +
                    BookDatabaseContract.PageEntry.COLUMN_NAME_PART_NUMBER + "=?" + SQL.AND +
                    BookDatabaseContract.PageEntry.COLUMN_NAME_PAGE_NUMBER + "=?)",
            new String[]{String.valueOf(partNumber), String.valueOf(pageNumber)}) > 0L;
}
 

long findMatchingGrantsCount(int uid, String authTokenType, Account account) {
    SQLiteDatabase db = mDeDatabase.getReadableDatabase();
    String[] args = {String.valueOf(uid), authTokenType, account.name, account.type};
    return DatabaseUtils.longForQuery(db, COUNT_OF_MATCHING_GRANTS, args);
}
 

long findMatchingGrantsCountAnyToken(int uid, Account account) {
    SQLiteDatabase db = mDeDatabase.getReadableDatabase();
    String[] args = {String.valueOf(uid), account.name, account.type};
    return DatabaseUtils.longForQuery(db, COUNT_OF_MATCHING_GRANTS_ANY_TOKEN, args);
}
 

public void sampleDatabaseUtils(DatabaseUtils databaseUtils, String input) {
    databaseUtils.longForQuery(null, input, null);
    databaseUtils.stringForQuery(null, input, null);
    databaseUtils.blobFileDescriptorForQuery(null, input, null);
    databaseUtils.createDbFromSqlStatements(null, null, 0, input);
}
 

@Override
public long getTotalTweetsEverSeen () {
	return DatabaseUtils.longForQuery(this.mDb, "SELECT max(" + TBL_TW_ID + ") FROM " + TBL_TW, null);
}
 

/**
 * Returns the maximum size the database may grow to.
 *
 * @return the new maximum database size
 */
public long getMaximumSize() {
    long pageCount = DatabaseUtils.longForQuery(this, "PRAGMA max_page_count;", null);
    return pageCount * getPageSize();
}
 

/**
 * Returns the current database page size, in bytes.
 *
 * @return the database page size, in bytes
 */
public long getPageSize() {
    return DatabaseUtils.longForQuery(this, "PRAGMA page_size;", null);
}