Szybkie zapytanie w MySQL, ale powolne w PHP

Question

Mamy wyszukiwarkę na jednej z naszych stron, która jest bardzo powolna. Włączyłem wolny dziennik zapytań i zarejestrowałem wszystkie zapytania, które trwały dłużej niż 10 sekund. Rejestrowane są tylko zapytania z tej wyszukiwarki. Oto jeden z przykładów dzienniku:

# Time: 120801 9:21:42 
# User@Host: ********** @ localhost [] 
# Query_time: 22.156250 Lock_time: 0.000000 Rows_sent: 33 Rows_examined: 3385401 
SET timestamp=1343805702; 
SELECT *, IF(InSection OR InBranche, 1, 0) AS SorteerKolom FROM(SELECT DISTINCT Plant, Email, Nicename, Displayname, JobTitle, Department, Initials, Lastname, LastnameForSort, 
           search_people.ForeignId, IsVennoot, 
           (Zoekwoorden LIKE '%statutair%') AS SearchTerm, 
           (Displayname LIKE '%statutair%') AS ByName, 
           0 AS InSection, 0 AS InBranche, 1 AS ShowAll, 
           (SELECT COUNT(*) FROM search_hasarticles WHERE UserId = search_people.ForeignId) > 0 AS HasWritten 
          FROM search_people 
          LEFT JOIN search_people_branches ON search_people.ForeignId = search_people_branches.UserId 
          LEFT JOIN search_people_specialismen ON search_people.ForeignId = search_people_specialismen.UserId 
          LEFT JOIN wp_usermeta AS wpu ON (wpu.user_id = search_people.ForeignId) 
          WHERE 
          (
           Firstname LIKE '%statutair%' 
           OR Lastname LIKE '%statutair%' 
           AND Displayname LIKE '%statutair%' 
           OR Email LIKE '%statutair%' 
           OR Address LIKE '%statutair%' 
           OR Initials LIKE '%statutair%' 
           OR Location LIKE '%statutair%' 
           OR Givenname LIKE '%statutair%' 
           OR Nickname LIKE '%statutair%' 
           OR JobTitle LIKE '%statutair%' 
           OR Login LIKE '%statutair%' 
           OR Title LIKE '%statutair%' 
           OR Phone LIKE '%statutair%' 
           OR Fax LIKE '%statutair%' 
           OR Plant LIKE '%statutair%' 
           OR Displayname LIKE '%statutair%' 
           OR Zoekwoorden LIKE '%statutair%' 

          ) 
          AND (1=1) AND search_people.IsHidden = 0 AND search_people.Activated = 1 UNION SELECT DISTINCT Plant, Email, Nicename, Displayname, JobTitle, Department, Initials, Lastname, LastnameForSort, 
           search_people.ForeignId, IsVennoot, 0 AS SearchTerm, 0 AS ByName, 0 AS InSection, 1 AS InBranche, 1 AS ShowAll, 
           (SELECT COUNT(*) FROM search_hasarticles WHERE UserId = search_people.ForeignId) > 0 AS HasWritten 
          FROM search_people 
          LEFT JOIN search_people_branches ON search_people.ForeignId = search_people_branches.UserId 
          LEFT JOIN search_branches ON search_branches.ForeignId = search_people_branches.BrancheId 
          LEFT JOIN search_people_specialismen ON search_people.ForeignId = search_people_specialismen.UserId 
          WHERE Name LIKE '%statutair%' AND (1=1) AND search_people.IsHidden = 0 AND search_people.Activated = 1 UNION SELECT DISTINCT Plant, Email, Nicename, Displayname, JobTitle, Department, Initials, Lastname, LastnameForSort, search_people.ForeignId, IsVennoot, 0 AS SearchTerm, 0 AS ByName, 1 AS InSection, 0 AS InBranche, 1 AS ShowAll, (SELECT COUNT(*) FROM search_hasarticles WHERE UserId = search_people.ForeignId) > 0 AS HasWritten FROM search_people LEFT JOIN search_people_specialismen ON search_people.ForeignId=search_people_specialismen.UserId LEFT JOIN search_specialties ON search_specialties.ForeignId=search_people_specialismen.SpecialismeId LEFT JOIN search_people_branches ON search_people.ForeignId=search_people_branches.UserId WHERE (Name LIKE '%statutair%' OR SearchTerms LIKE '%statutair%') AND (1=1) AND search_people.IsHidden = 0 AND search_people.Activated = 1 UNION SELECT DISTINCT Plant, Email, Nicename, Displayname, JobTitle, Department, Initials, Lastname, LastnameForSort, search_people.ForeignId, IsVennoot, 0 AS SearchTerm, 0 AS ByName, 0 AS InSection, 0 AS InBranche, 0 AS ShowAll, 1 AS HasWritten FROM search_posts LEFT JOIN search_posts_branches ON search_posts.ForeignId=search_posts_branches.PostId LEFT JOIN search_branches ON search_posts_branches.BrancheId=search_branches.ForeignId LEFT JOIN search_people_specialismen ON search_posts.PostAuthor=search_people_specialismen.UserId LEFT JOIN search_specialties ON search_people_specialismen.SpecialismeId=search_specialties.ForeignId INNER JOIN search_people ON search_people.ForeignId=search_posts.PostAuthor WHERE (PostTitle LIKE '%statutair%' OR PostContent LIKE '%statutair%' OR search_branches.Name LIKE '%statutair%' OR search_specialties.Name LIKE '%statutair%') AND PostStatus='publish' AND PostType='post' AND (1=1) AND search_people.IsHidden = 0 AND search_people.Activated = 1) AS search_results ORDER BY SearchTerm DESC, ByName DESC, SorteerKolom DESC, IsVennoot DESC, InSection DESC, InBranche DESC, HasWritten DESC, LastnameForSort ASC, Initials ASC; 

Jak widać zapytanie trwało około 22 sekund, aby wykonać, jeśli to samo zapytanie bezpośrednio w MySQL trwa około 4 sekund.

Zrobiłem Wyjaśnij na tej samej kwerendy i uotput się następująco:

id        select_type      table       type        possible_keys     key        key_len       ref        rows        Extra          
1        PRIMARY       <derived2>      ALL        NULL        NULL        NULL        NULL        33        Using filesort       
2        DERIVED       search_people     ALL        NULL        NULL        NULL        NULL        323        Using where; Using temporary    
2        DERIVED       search_people_branches   ALL        NULL        NULL        NULL        NULL        2013        Distinct         
2        DERIVED       search_people_specialismen  ALL        NULL        NULL        NULL        NULL        1013        Distinct         
2        DERIVED       wpu        ref        user_id       user_id       8        wordpress.search_people.ForeignId 84        Using index; Distinct      
3        DEPENDENT SUBQUERY    search_hasarticles    ALL        NULL        NULL        NULL        NULL        101        Using where        
4        UNION       search_branches     ALL        NULL        NULL        NULL        NULL        19        Using where; Using temporary    
4        UNION       search_people     ALL        NULL        NULL        NULL        NULL        323        Using where; Using join buffer   
4        UNION       search_people_specialismen  ALL        NULL        NULL        NULL        NULL        1013        Distinct         
4        UNION       search_people_branches   ALL        NULL        NULL        NULL        NULL        2013        Using where; Distinct; Using join buffer 
5        DEPENDENT SUBQUERY    search_hasarticles    ALL        NULL        NULL        NULL        NULL        101        Using where        
6        UNION       search_specialties    ALL        NULL        NULL        NULL        NULL        73        Using where; Using temporary    
6        UNION       search_people     ALL        NULL        NULL        NULL        NULL        323        Using where; Using join buffer   
6        UNION       search_people_specialismen  ALL        NULL        NULL        NULL        NULL        1013        Using where; Distinct; Using join buffer 
6        UNION       search_people_branches   ALL        NULL        NULL        NULL        NULL        2013        Distinct         
7        DEPENDENT SUBQUERY    search_hasarticles    ALL        NULL        NULL        NULL        NULL        101        Using where        
8        UNION       search_posts      ALL        NULL        NULL        NULL        NULL        15860       Using where; Using temporary    
8        UNION       search_posts_branches   ALL        NULL        NULL        NULL        NULL        149        Distinct         
8        UNION       search_branches     ALL        NULL        NULL        NULL        NULL        19        Distinct         
8        UNION       search_people_specialismen  ALL        NULL        NULL        NULL        NULL        1013        Distinct         
8        UNION       search_specialties    ALL        NULL        NULL        NULL        NULL        73        Using where; Distinct      
8        UNION       search_people     ALL        NULL        NULL        NULL        NULL        323        Using where; Distinct; Using join buffer 
           UNION RESULT      <union2,4,6,8>     ALL        NULL        NULL        NULL        NULL        NULL                  

Czy ktoś może wyjaśnić, dlaczego to samo zapytanie jest taaak dużo wolniej na mojej stronie internetowej, a następnie kierować się w MySQL? A co ważniejsze, czy istnieje sposób na przyspieszenie tego zapytania na tej stronie?

Jeśli potrzebujesz więcej informacji, aby rozwiązać problem, daj okrzyk, a ja postaram się je zapewnić.

Dzięki tak dużo wcześniej, Jan.

jest to profil zapytania:

+----------------------+----------+ 
| Status    | Duration | 
+----------------------+----------+ 
| starting    | 0.000431 | 
| Opening tables  | 0.002004 | 
| System lock   | 0.000012 | 
| Table lock   | 0.000502 | 
| optimizing   | 0.000033 | 
| statistics   | 0.000042 | 
| preparing   | 0.000034 | 
| Creating tmp table | 0.000085 | 
| executing   | 0.000004 | 
| Copying to tmp table | 0.001957 | 
| Sending data   | 0.000006 | 
| optimizing   | 0.000025 | 
| statistics   | 0.000027 | 
| preparing   | 0.000041 | 
| Creating tmp table | 0.000114 | 
| executing   | 0.000001 | 
| Copying to tmp table | 0.000058 | 
| Sending data   | 0.000004 | 
| optimizing   | 0.000021 | 
| statistics   | 0.000027 | 
| preparing   | 0.000037 | 
| Creating tmp table | 0.000095 | 
| executing   | 0.000003 | 
| Copying to tmp table | 0.007376 | 
| optimizing   | 0.000013 | 
| statistics   | 0.000017 | 
| preparing   | 0.000011 | 
| executing   | 0.000005 | 
| Sending data   | 0.001248 | 
| executing   | 0.000014 | 
| Sending data   | 0.001894 | 
| executing   | 0.000007 | 
| Sending data   | 0.003249 | 
| executing   | 0.000004 | 
| Sending data   | 0.001487 | 
| executing   | 0.000001 | 
| Sending data   | 0.000433 | 
| executing   | 0.000001 | 
| Sending data   | 0.012100 | 
| executing   | 0.000006 | 
| Sending data   | 0.000713 | 
| executing   | 0.000002 | 
| Sending data   | 0.000681 | 
| executing   | 0.000001 | 
| Sending data   | 0.015382 | 
| executing   | 0.000005 | 
| Sending data   | 0.001048 | 
| executing   | 0.000002 | 
| Sending data   | 0.000916 | 
| executing   | 0.000004 | 
| Sending data   | 0.000421 | 
| executing   | 0.000001 | 
| Sending data   | 0.000561 | 
| executing   | 0.000001 | 
| Sending data   | 0.005126 | 
| executing   | 0.000008 | 
| Sending data   | 0.014534 | 
| executing   | 0.000004 | 
| Sending data   | 0.001666 | 
| executing   | 0.000006 | 
| Sending data   | 0.001641 | 
| Sending data   | 0.000203 | 
| optimizing   | 0.000045 | 
| statistics   | 0.000050 | 
| preparing   | 0.000049 | 
| Creating tmp table | 0.000182 | 
| executing   | 0.000002 | 
| Copying to tmp table | 5.101209 | 
| Sending data   | 0.000226 | 
| optimizing   | 0.000007 | 
| statistics   | 0.000008 | 
| preparing   | 0.000007 | 
| executing   | 0.000001 | 
| Sending data   | 0.000217 | 
| removing tmp table | 0.000044 | 
| Sending data   | 0.000007 | 
| removing tmp table | 0.000012 | 
| Sending data   | 0.000017 | 
| removing tmp table | 0.000011 | 
| Sending data   | 0.000005 | 
| removing tmp table | 0.000033 | 
| Sending data   | 0.000008 | 
| removing tmp table | 0.000030 | 
| Sending data   | 0.000009 | 
| init     | 0.000044 | 
| optimizing   | 0.000005 | 
| statistics   | 0.000004 | 
| preparing   | 0.000007 | 
| executing   | 0.000002 | 
| Sorting result  | 0.000074 | 
| Sending data   | 0.000164 | 
| end     | 0.000003 | 
| query end   | 0.000005 | 
| freeing items  | 0.000210 | 
| removing tmp table | 0.000061 | 
| closing tables  | 0.000051 | 
| logging slow query | 0.000003 | 
| cleaning up   | 0.000026 | 
+----------------------+----------+ 

Answer 1

Wydaje mi się, że trzeba ustawić indeks na wielu kolumnach. Przeczytaj to: http://dev.mysql.com/doc/refman/5.0/en/explain-output.html Aby przyspieszyć zapytanie, zacznij od ustawienia indeksu dla każdej kolumny używanej w instrukcjach JOIN. Jeśli to nie przyspieszy, ustaw indeks kolumn, na których sprawdzasz GDZIEGO. Również operator OR jest powolny, a w bloku z wszystkimi operatorami operacyjnymi jest również AND. A może możesz pominąć kilka z tych OR, jak "inicjały" (ale to oczywiście dzikie domysły ...)

Answer 2

widzę dużo non-wymiennymi warunkach, takich jak Firstname LIKE '%statutair%'. Istnieje możliwość, że MySQL faktycznie używa swojego results cache, podczas gdy PHP nie jest w stanie wykorzystać pamięci podręcznej wyników. Może się tak zdarzyć, na przykład, jeśli używasz PDO z ATTR_EMULATE_PREPARES option disabled.

Aby dowiedzieć się, dodać klauzulę SQL_NO_CACHE podczas testowania od wewnątrz MySQL, jak w:

SELECT SQL_NO_CACHE id, name FROM customer;