从多个数据库文件中选择所有行-PHP sqlite3

Question

I have multiple db files which contains the same table with different values.

example files:

wifi_16-09-02_09_34_03.db

wifi_16-09-02_09_44_06.db

wifi_16-09-02_09_60_02.db

How can I select all the rows from multiple files?

I only know to do this with one file.

Here is my code:

  $dbfile = 'wifi_16-09-02_09_34_03.db';
  $db = new SQLite3('dbs/'.$dbfile);
  $sql = 'SELECT * FROM wifi';
  $results = $db->query($sql);

I am new on SQLite3 , any help would be appreciated.

Answer 1

You can simply open the other databases in the same way.

If you want to have all rows in a single query, you need to attach all the other databases to some main database, and use a compound query :

$db->exec("ATTACH 'dbs/wifi_16-09-02_09_44_06.db' AS db2");
$db->exec("ATTACH 'dbs/wifi_16-09-02_09_60_02.db' AS db3");
...
$sql = <<<'SQL'
    SELECT * FROM main.wifi
    UNION ALL
    SELECT * FROM db2.wifi
    UNION ALL
    SELECT * FROM db3.wifi
SQL;
$results = $db->query($sql);