sqlite使用php获取EXPLAIN QUERY PLAN结果

Question

How must I execute EXPLAIN QUERY PLAN command to sqlite to get results and show them on the screen with php ? I use simple Sqlite3 php class http://nl1.php.net/manual/en/class.sqlite3.php , but query() return SQLite3Result object, not the raw dump.

 $result = $db->query("EXPLAIN QUERY PLAN SELECT * from events WHERE type='comment' AND TIMESTAMP > $time AND PAGE = '$page' LIMIT 1");
 echo $result;

Answer 1

EXPLAIN QUERY PLAN behaves like a query that outputs a four-column table:

sqlite> .mode columns
sqlite> .header on
sqlite> EXPLAIN QUERY PLAN SELECT 1 UNION SELECT 2 GROUP BY 1 ORDER BY 1;
selectid    order       from        detail                      
----------  ----------  ----------  ----------------------------
2           0           0           USE TEMP B-TREE FOR ORDER BY
0           0           0           COMPOUND SUBQUERIES 1 AND 2 

You have to output it like a query, i.e., loop over the rows, and print the value in each column.

You might want to use the sqlite3 command-line shell instead.