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Mengambil Baris Tunggal dari Tabel Gabung

Setelah melihat jawaban lain, ini membantu saya menyadari masalah mendasar.

Tabel artikel dan tabel article_images keduanya harus memiliki indeks tambahan.

Inilah yang Anda miliki sekarang:

CREATE TABLE `articles` (
    `id` int(10) unsigned not null auto_increment,
    `author_id` int(10) unsigned not null,
    `date_created` datetime not null,
    PRIMARY KEY(id)
) ENGINE=InnoDB;

CREATE TABLE `article_images` (
    `article_id` int(10) unsigned not null,
    `filename` varchar(100) not null,
    `date_added` datetime not null,
    UNIQUE INDEX(article_id, filename)
) ENGINE=InnoDB;

Inilah yang Anda butuhkan:

CREATE TABLE `articles` (
    `id` int(10) unsigned not null auto_increment,
    `author_id` int(10) unsigned not null,
    `date_created` datetime not null,
    PRIMARY KEY(id),
    INDEX (date_created DESC)
) ENGINE=InnoDB;

CREATE TABLE `article_images` (
    `article_id` int(10) unsigned not null,
    `filename` varchar(100) not null,
    `date_added` datetime not null,
    UNIQUE INDEX (article_id, filename),
    INDEX (article_id, date_added),
) ENGINE=InnoDB;

artikel
Indeks baru untuk mengurutkan artikel menurut tanggal penyisipan dalam urutan menurun

article_images
Indeks pertama masih diperlukan karena akan menjaga agar tidak melampirkan gambar lain dengan nama file yang sama ke sebuah artikel.
Indeks kedua akan mempermudah pencarian gambar terbaru,

Dengan indeks baru tersebut, inilah kueri yang akan melakukan penawaran Anda:

  SELECT
    AAA.author_id,
    AAA.date_created,
    IFNULL(BBB.title,'<NO_TITLE>') title,
    IFNULL(CCC.filename,'<NO-IMAGE>') filename
  FROM
  (
    SELECT
      AA.id,
      AA.date_added,
      BB.author_id,
      BB.date_created
    FROM
    (
      SELECT
        A.id,IFNULL(MAX(B.date_added),'1900-01-01 00:00:00') date_added
        FROM (SELECT id FROM articles ORDER BY date_created DESC LIMIT 40) A
        LEFT JOIN article_images B ON A.id = B.article_id
        GROUP BY A.id
    ) AA
    INNER JOIN articles BB USING (id)
  ) AAA
  LEFT JOIN article_contents BBB ON AAA.id=BBB.article_id
  LEFT JOIN article_images CCC
  ON (AAA.id=CCC.article_id AND AAA.date_added=CCC.date_added)
  ORDER BY AAA.date_created DESC;

Tujuannya adalah pertama untuk membuat subquery internal yang hanya memiliki 40 baris. Itulah yang harus dibawa kembali oleh AA. Subquery AAA harus memiliki info artikel ditambah tanggal gambar terakhir dimasukkan. Kumpulan gabungan terakhir harus menghubungkan 40 id dengan judul dan gambar. Langkah terakhir adalah menyajikan hasil yang diatur dalam urutan menurun.

Karena saya tidak memiliki data sampel, saya menulis tiga prosedur tersimpan dalam database sampel yang disebut barang

1 untuk membuat tabel

DELIMITER $$

DROP PROCEDURE IF EXISTS `stuff`.`MakeTables` $$
CREATE PROCEDURE `stuff`.`MakeTables` ()
BEGIN

DROP TABLE IF EXISTS articles;
DROP TABLE IF EXISTS article_contents;
DROP TABLE IF EXISTS article_images;

CREATE TABLE `articles` (
    `id` int(10) unsigned not null auto_increment,
    `author_id` int(10) unsigned not null,
    `date_created` datetime not null,
    PRIMARY KEY(id),
    INDEX (date_created DESC)
) ENGINE=InnoDB;

CREATE TABLE `article_contents` (
    `article_id` int(10) unsigned not null,
    `title` varchar(100) not null,
    `content` text not null,
PRIMARY KEY(article_id)) ENGINE=InnoDB;

CREATE TABLE `article_images` (
    `article_id` int(10) unsigned not null,
    `filename` varchar(100) not null,
    `date_added` datetime not null,
    UNIQUE INDEX (article_id, filename),
    INDEX (article_id, date_added)
) ENGINE=InnoDB;

END $$

DELIMITER ;

1 untuk membuat datanya

DELIMITER $$

DROP PROCEDURE IF EXISTS `stuff`.`LoadSampleData` $$
CREATE PROCEDURE `stuff`.`LoadSampleData` ()
BEGIN

    DECLARE x,y,z INT;

    SET x = 1;
    WHILE x <= 100 DO
        INSERT INTO articles (author_id,date_created) VALUES
        (RAND() * POWER(2,31),
        DATE('1970-01-01 00:00:00') + INTERVAL (RAND() * POWER(2,30)) SECOND);
        SET x = x + 1;
    END WHILE;

    SET x = 1;
    WHILE x <= 100 DO
        SET y = FLOOR(RAND() * 100);
        IF y >= 30 THEN
            INSERT INTO article_contents
            VALUES (x,
            CONCAT('TITLE_',FLOOR(RAND() * POWER(2,31))),
            CONCAT('CONTENT_',FLOOR(RAND() * POWER(2,31))));
        END IF;
        SET x = x + 1;
    END WHILE;

    SET x = 1;
    WHILE x <= 100 DO
        SELECT COUNT(1) INTO y FROM article_contents WHERE article_id = x;
        IF y = 1 THEN
            SET y = 0;
            WHILE y < 20 DO
                SET y = y + 1;
                SET z = FLOOR(RAND() * 10);
                IF z >= 5 THEN
                    INSERT INTO article_images
                    VALUES (x,
                    CONCAT('IMAGE_',FLOOR(RAND() * POWER(2,31))),
                    DATE('1970-01-01 00:00:00') + INTERVAL (RAND() * POWER(2,30)) SECOND);
                END IF;
            END WHILE;
        END IF;
        SET x = x + 1;
    END WHILE;

    SELECT COUNT(1) INTO x FROM articles;
    SELECT COUNT(1) INTO y FROM article_contents;
    SELECT COUNT(1) INTO z FROM article_images;

    SELECT CONCAT('Articles:',x,' Titles:',y,' Images: ',z) Results;

END $$

DELIMITER ;

1 untuk menjalankan kueri

DELIMITER $$

DROP PROCEDURE IF EXISTS `stuff`.`ShowLast40` $$
CREATE PROCEDURE `stuff`.`ShowLast40` ()
BEGIN

  SELECT
    AAA.author_id,
    AAA.date_created,
    IFNULL(BBB.title,'<NO_TITLE>') title,
    IFNULL(CCC.filename,'<NO-IMAGE>') filename
  FROM
  (
    SELECT
      AA.id,
      AA.date_added,
      BB.author_id,
      BB.date_created
    FROM
    (
      SELECT
        A.id,IFNULL(MAX(B.date_added),'1900-01-01 00:00:00') date_added
        FROM (SELECT id FROM articles ORDER BY date_created DESC LIMIT 40) A
        LEFT JOIN article_images B ON A.id = B.article_id
        GROUP BY A.id
    ) AA
    INNER JOIN articles BB USING (id)
  ) AAA
  LEFT JOIN article_contents BBB ON AAA.id=BBB.article_id
  LEFT JOIN article_images CCC
  ON (AAA.id=CCC.article_id AND AAA.date_added=CCC.date_added)
  ORDER BY AAA.date_created DESC;

END $$

DELIMITER ;

Berikut adalah contoh output ketika saya menjalankannya di Desktop Windows saya (MySQL 5.5.12):

mysql> call maketables; call loadsampledata;
Query OK, 0 rows affected (0.31 sec)

+------------------------------------+
| Results                            |
+------------------------------------+
| Articles:100 Titles:67 Images: 666 |
+------------------------------------+
1 row in set (23.73 sec)

mysql> call showlast40;
+------------+---------------------+------------------+------------------+
| author_id  | date_created        | title            | filename         |
+------------+---------------------+------------------+------------------+
| 1576679519 | 2004-01-02 14:05:17 | TITLE_1757853515 | IMAGE_1601858163 |
|  992840519 | 2003-05-17 05:48:11 | TITLE_319026350  | IMAGE_1913708631 |
| 1366977197 | 2003-03-20 19:37:23 | <NO_TITLE>       | <NO-IMAGE>       |
| 1705517382 | 2003-02-07 16:48:56 | <NO_TITLE>       | <NO-IMAGE>       |
| 1529899841 | 2002-11-02 20:59:26 | <NO_TITLE>       | <NO-IMAGE>       |
| 1756824942 | 2002-08-28 16:01:59 | <NO_TITLE>       | <NO-IMAGE>       |
|  175825630 | 2002-05-08 13:48:56 | TITLE_240812804  | IMAGE_1214850809 |
|  757530551 | 2002-02-08 00:20:17 | TITLE_4447486    | IMAGE_1511850161 |
|  840251261 | 2002-01-25 20:06:56 | TITLE_1160842143 | IMAGE_206027488  |
|  964653347 | 2001-12-26 19:15:47 | TITLE_1552408257 | IMAGE_717719932  |
| 2106039126 | 2001-11-11 17:09:29 | <NO_TITLE>       | <NO-IMAGE>       |
| 2085991608 | 2001-08-01 12:48:20 | <NO_TITLE>       | <NO-IMAGE>       |
| 1895462094 | 2000-12-02 05:31:41 | <NO_TITLE>       | <NO-IMAGE>       |
| 1589384729 | 2000-04-28 23:55:50 | TITLE_1040850308 | IMAGE_1200414639 |
|  514341550 | 2000-04-20 07:25:05 | TITLE_188288840  | IMAGE_164856430  |
|  887359583 | 2000-02-13 03:30:47 | <NO_TITLE>       | <NO-IMAGE>       |
| 1156687499 | 1999-06-16 00:29:17 | TITLE_686398996  | IMAGE_670200418  |
| 1561242593 | 1998-12-08 05:50:17 | <NO_TITLE>       | <NO-IMAGE>       |
| 1117889993 | 1998-10-23 17:02:44 | TITLE_1491217221 | IMAGE_649630126  |
|  740063135 | 1998-09-16 23:52:41 | TITLE_579374776  | IMAGE_757313192  |
|  429699232 | 1998-04-19 01:41:17 | TITLE_73748980   | IMAGE_1881818111 |
| 1827051060 | 1998-02-27 01:01:50 | TITLE_1588619991 | IMAGE_1657322715 |
| 1442984429 | 1997-11-19 21:23:35 | TITLE_184173382  | IMAGE_597809368  |
|  152267158 | 1997-05-02 20:25:50 | <NO_TITLE>       | <NO-IMAGE>       |
| 1323598169 | 1997-03-14 16:30:38 | TITLE_1355869397 | IMAGE_1058313818 |
|   66122740 | 1997-01-05 15:12:20 | TITLE_1259073183 | IMAGE_198280936  |
|    5161474 | 1996-06-28 10:47:26 | TITLE_1876022823 | IMAGE_1138098675 |
| 1865082792 | 1996-03-01 19:09:11 | TITLE_1288151615 | IMAGE_245974646  |
| 1923481146 | 1995-08-07 00:36:11 | TITLE_922744000  | IMAGE_2067090321 |
| 1725218958 | 1995-03-18 05:15:29 | TITLE_583120586  | IMAGE_592773824  |
|  117806248 | 1995-01-05 02:34:32 | <NO_TITLE>       | <NO-IMAGE>       |
| 1428777335 | 1993-06-06 01:52:32 | TITLE_661148588  | IMAGE_633345518  |
| 1091245943 | 1993-06-05 05:51:47 | TITLE_1407444563 | IMAGE_538936256  |
| 2088382260 | 1993-03-25 06:03:29 | TITLE_1144364681 | IMAGE_1790013089 |
|  625878569 | 1992-12-21 07:41:26 | TITLE_1319355723 | IMAGE_921580624  |
|  110555110 | 1992-01-01 20:49:59 | <NO_TITLE>       | <NO-IMAGE>       |
| 1110532475 | 1991-11-20 07:19:32 | <NO_TITLE>       | <NO-IMAGE>       |
| 1726795146 | 1990-10-09 00:23:44 | TITLE_782624350  | IMAGE_1760322575 |
|  370183888 | 1990-03-30 15:59:17 | <NO_TITLE>       | <NO-IMAGE>       |
| 1497483317 | 1990-02-19 01:25:41 | TITLE_776483948  | IMAGE_665824222  |
+------------+---------------------+------------------+------------------+
40 rows in set (0.00 sec)

Cobalah !!!

PERBARUI

Saya benar-benar memastikan bahwa 40 waktu yang Anda baca sebenarnya adalah 40 teratas. Memang benar. Saya menjalankan kueri:pilih * dari artikel ORDER BY date_created DESC; untuk memastikan.

PEMBARUAN 17-05-2011 14:06

mysql> call maketables; call loadsampledata;
Query OK, 0 rows affected (0.45 sec)

+-------------------------------------+
| Results                             |
+-------------------------------------+
| Articles:100 Titles:67 Images: 6739 |
+-------------------------------------+
1 row in set (3 min 45.45 sec)

Query OK, 0 rows affected (3 min 45.45 sec)

mysql> call showlast40;
+------------+---------------------+------------------+------------------+
| author_id  | date_created        | title            | filename         |
+------------+---------------------+------------------+------------------+
|  196582776 | 2004-01-05 14:09:04 | <NO_TITLE>       | <NO-IMAGE>       |
| 1880371016 | 2003-07-31 05:50:37 | TITLE_1191518827 | IMAGE_1562208019 |
|   22204986 | 2003-02-16 14:09:22 | <NO_TITLE>       | <NO-IMAGE>       |
|  355490160 | 2002-11-21 02:35:19 | <NO_TITLE>       | <NO-IMAGE>       |
|  869510149 | 2001-12-27 22:07:52 | TITLE_1528616779 | IMAGE_223327284  |
| 2063556512 | 2001-04-16 18:47:46 | TITLE_1839975091 | IMAGE_1282187005 |
|  529754190 | 2000-07-14 19:44:01 | TITLE_1557423205 | IMAGE_1931606737 |
|  166226262 | 1999-11-08 03:27:22 | <NO_TITLE>       | <NO-IMAGE>       |
| 1981417562 | 1999-09-11 12:59:10 | TITLE_198262896  | IMAGE_1491273871 |
|  831057001 | 1999-06-14 15:06:31 | TITLE_1170272131 | IMAGE_760396200  |
| 1454252623 | 1998-06-02 08:35:46 | <NO_TITLE>       | <NO-IMAGE>       |
| 1435450777 | 1997-11-17 18:10:34 | TITLE_482497458  | IMAGE_1331932705 |
| 1536315541 | 1997-11-02 05:24:49 | <NO_TITLE>       | <NO-IMAGE>       |
| 2078028530 | 1997-03-14 22:36:58 | TITLE_321332010  | IMAGE_1897983295 |
|  701651581 | 1997-01-13 22:36:58 | TITLE_1337390701 | IMAGE_1630983859 |
|  101442444 | 1996-11-22 09:40:16 | <NO_TITLE>       | <NO-IMAGE>       |
|   51114930 | 1996-11-20 03:24:49 | TITLE_1866751135 | IMAGE_1669595407 |
|  722056183 | 1996-08-03 15:23:01 | <NO_TITLE>       | <NO-IMAGE>       |
| 1178720989 | 1996-06-29 22:47:19 | TITLE_579734376  | IMAGE_833229222  |
|  511355958 | 1996-03-10 09:32:46 | TITLE_1540275289 | IMAGE_1168117261 |
|  831921829 | 1996-01-31 06:36:04 | TITLE_661038882  | IMAGE_1199197195 |
| 1288455163 | 1995-08-22 00:34:25 | TITLE_1599332515 | IMAGE_822445764  |
| 1976208956 | 1995-06-02 09:23:01 | TITLE_58372998   | IMAGE_793318650  |
| 2092066982 | 1995-03-28 20:35:37 | TITLE_1693142377 | IMAGE_1176935479 |
| 1083841549 | 1994-07-11 18:46:52 | TITLE_1955674591 | IMAGE_1240485919 |
|  359037132 | 1994-07-11 02:44:19 | TITLE_713454936  | IMAGE_1072569732 |
| 1471985773 | 1994-05-10 17:08:01 | TITLE_1065017724 | IMAGE_393097704  |
| 1888864730 | 1994-01-15 17:41:28 | TITLE_1060275498 | IMAGE_230810100  |
| 1688028488 | 1993-12-28 06:36:58 | <NO_TITLE>       | <NO-IMAGE>       |
| 1739777948 | 1993-02-15 00:30:31 | TITLE_1226842225 | IMAGE_1615058467 |
|  445721334 | 1991-12-15 20:54:49 | TITLE_1336145587 | IMAGE_2114729323 |
| 1661002442 | 1991-06-30 05:49:34 | TITLE_151142910  | IMAGE_1623325381 |
| 2092223006 | 1991-06-13 13:15:58 | TITLE_33175860   | IMAGE_1225117771 |
| 1553434585 | 1991-01-12 03:34:25 | TITLE_728483442  | IMAGE_1954153339 |
|  528544608 | 1990-11-10 08:21:04 | <NO_TITLE>       | <NO-IMAGE>       |
| 1043927395 | 1990-10-05 00:48:49 | TITLE_304307448  | IMAGE_1702062493 |
| 1685702960 | 1990-04-28 05:44:19 | TITLE_1909853341 | IMAGE_263553036  |
| 1392428383 | 1990-03-07 15:08:46 | <NO_TITLE>       | <NO-IMAGE>       |
|  643714153 | 1990-02-14 08:32:10 | TITLE_837416724  | IMAGE_1673964259 |
| 2132028206 | 1989-09-28 16:04:07 | TITLE_614908878  | IMAGE_1362210487 |
+------------+---------------------+------------------+------------------+
40 rows in set (0.01 sec)

Semuanya berfungsi seperti yang saya publikasikan sebelumnya bahkan dengan kumpulan gambar yang lebih besar. Berikut adalah kueri dari Prosedur Tersimpan ShowLast40:

  SELECT
    AAA.author_id,
    AAA.date_created,
    IFNULL(BBB.title,'<NO_TITLE>') title,
    IFNULL(CCC.filename,'<NO-IMAGE>') filename
  FROM
  (
    SELECT
      AA.id,
      AA.date_added,
      BB.author_id,
      BB.date_created
    FROM
    (
      SELECT
        A.id,IFNULL(MAX(B.date_added),'1900-01-01 00:00:00') date_added
        FROM (SELECT id FROM articles ORDER BY date_created DESC LIMIT 40) A
        LEFT JOIN article_images B ON A.id = B.article_id
        GROUP BY A.id
    ) AA
    INNER JOIN articles BB USING (id)
  ) AAA
  LEFT JOIN article_contents BBB ON AAA.id=BBB.article_id
  LEFT JOIN article_images CCC
  ON (AAA.id=CCC.article_id AND AAA.date_added=CCC.date_added)
  ORDER BY AAA.date_created DESC;

PERBARUI 17-05-2011 15:16

Hanya untuk tertawa, saya meningkatkan sampel dan memutar ulang. Kecepatan kueri yang sama.

mysql> call maketables; call loadsampledata; call showlast40;
Query OK, 0 rows affected (0.38 sec)

+----------------------------------------+
| Results                                |
+----------------------------------------+
| Articles:1000 Titles:886 Images: 88596 |
+----------------------------------------+
1 row in set (51 min 22.29 sec)

Query OK, 0 rows affected (51 min 22.29 sec)

+------------+---------------------+------------------+------------------+
| author_id  | date_created        | title            | filename         |
+------------+---------------------+------------------+------------------+
| 1464539515 | 2004-01-07 22:45:04 | TITLE_676010724  | IMAGE_1877060293 |
|  272558724 | 2004-01-03 23:44:19 | TITLE_1213504045 | IMAGE_550812606  |
| 2000476448 | 2003-12-28 18:05:10 | TITLE_1762951489 | IMAGE_1201290847 |
|  955209697 | 2003-12-25 00:55:43 | TITLE_1064749344 | IMAGE_1335865507 |
| 1657429856 | 2003-12-19 01:03:13 | TITLE_1931852743 | IMAGE_905288424  |
|  759381001 | 2003-11-12 10:46:52 | TITLE_878255772  | IMAGE_2014780795 |
| 1269478951 | 2003-11-06 02:06:22 | TITLE_2026098781 | IMAGE_982272966  |
| 1049672131 | 2003-10-04 20:55:34 | TITLE_2043080215 | IMAGE_987859662  |
| 1429108729 | 2003-09-16 19:07:52 | TITLE_424483080  | IMAGE_35379150   |
| 1672198676 | 2003-09-13 11:49:52 | TITLE_1131552745 | IMAGE_875049630  |
| 1645878842 | 2003-08-24 13:42:04 | TITLE_1077302833 | IMAGE_702269538  |
|  172347180 | 2003-08-21 14:26:37 | TITLE_558691044  | IMAGE_1091183587 |
| 1137674509 | 2003-08-15 08:44:37 | TITLE_1982979709 | IMAGE_1234487941 |
|  282998112 | 2003-08-05 10:01:34 | TITLE_353831568  | IMAGE_738487608  |
|  246145344 | 2003-08-02 00:42:31 | TITLE_376954044  | IMAGE_1279375459 |
|  218409162 | 2003-07-14 02:55:16 | TITLE_1932540991 | IMAGE_1078689211 |
|  593263087 | 2003-07-12 22:47:01 | TITLE_1604012533 | IMAGE_834822870  |
| 2115914174 | 2003-07-06 03:06:31 | TITLE_1268165545 | IMAGE_1068632322 |
|  552557275 | 2003-07-01 16:45:22 | TITLE_2022112717 | IMAGE_1410588295 |
| 1500437041 | 2003-06-29 20:05:19 | TITLE_35559258   | IMAGE_159953586  |
| 1098371257 | 2003-06-09 07:29:37 | TITLE_1694076415 | IMAGE_1409619391 |
| 1570373503 | 2003-05-22 16:45:04 | TITLE_125157894  | IMAGE_723393492  |
| 1330507411 | 2003-05-05 21:40:07 | TITLE_1571250589 | IMAGE_701840418  |
| 1666035620 | 2003-04-26 02:51:40 | TITLE_504713706  | IMAGE_1410357553 |
| 1458179791 | 2003-04-19 05:34:25 | <NO_TITLE>       | <NO-IMAGE>       |
| 1365758305 | 2003-03-28 10:09:58 | TITLE_704554170  | IMAGE_2085080137 |
| 2131082774 | 2003-03-26 16:43:25 | TITLE_1411034929 | IMAGE_303539208  |
|  103396632 | 2003-02-14 09:11:28 | TITLE_915927396  | IMAGE_1381045723 |
|  396479202 | 2003-02-01 15:51:40 | <NO_TITLE>       | <NO-IMAGE>       |
| 2019916250 | 2003-01-30 00:44:46 | <NO_TITLE>       | <NO-IMAGE>       |
|  431091906 | 2003-01-29 13:08:37 | <NO_TITLE>       | <NO-IMAGE>       |
|  705166549 | 2003-01-23 21:37:07 | TITLE_1530318643 | IMAGE_257673696  |
| 1278327049 | 2002-12-31 16:39:40 | TITLE_772845324  | IMAGE_1355754913 |
| 1871174528 | 2002-12-30 19:03:40 | TITLE_65725764   | IMAGE_522904938  |
|  611892727 | 2002-12-22 10:19:07 | TITLE_333758274  | IMAGE_734815032  |
|  758497849 | 2002-12-04 15:05:10 | TITLE_129140574  | IMAGE_244407066  |
|  518111034 | 2002-10-17 16:38:10 | TITLE_1976498683 | IMAGE_2008599775 |
| 1737725786 | 2002-10-15 23:52:52 | TITLE_1441053871 | IMAGE_1595265847 |
| 1206055789 | 2002-10-03 22:07:52 | TITLE_562697952  | IMAGE_198940092  |
|  702790153 | 2002-08-31 17:37:16 | TITLE_1788304903 | IMAGE_1212944101 |
+------------+---------------------+------------------+------------------+
40 rows in set (0.01 sec)

Query OK, 0 rows affected (0.01 sec)

PEMBARUAN 17-05-2011 15:40

Berikut adalah output baru termasuk tanggal gambar terbaru:

mysql> call showlast40;
+------------+---------------------+------------------+------------------+---------------------+
| author_id  | date_created        | title            | filename         | image_date          |
+------------+---------------------+------------------+------------------+---------------------+
| 1464539515 | 2004-01-07 22:45:04 | TITLE_676010724  | IMAGE_1877060293 | 2003-10-16 02:06:58 |
|  272558724 | 2004-01-03 23:44:19 | TITLE_1213504045 | IMAGE_550812606  | 2003-12-28 07:25:43 |
| 2000476448 | 2003-12-28 18:05:10 | TITLE_1762951489 | IMAGE_1201290847 | 2003-08-31 16:56:01 |
|  955209697 | 2003-12-25 00:55:43 | TITLE_1064749344 | IMAGE_1335865507 | 2003-11-11 18:37:07 |
| 1657429856 | 2003-12-19 01:03:13 | TITLE_1931852743 | IMAGE_905288424  | 2003-09-26 07:20:01 |
|  759381001 | 2003-11-12 10:46:52 | TITLE_878255772  | IMAGE_2014780795 | 2003-09-30 06:54:40 |
| 1269478951 | 2003-11-06 02:06:22 | TITLE_2026098781 | IMAGE_982272966  | 2003-07-28 11:59:10 |
| 1049672131 | 2003-10-04 20:55:34 | TITLE_2043080215 | IMAGE_987859662  | 2003-11-19 05:26:37 |
| 1429108729 | 2003-09-16 19:07:52 | TITLE_424483080  | IMAGE_35379150   | 2003-11-18 22:17:55 |
| 1672198676 | 2003-09-13 11:49:52 | TITLE_1131552745 | IMAGE_875049630  | 2003-06-08 00:42:58 |
| 1645878842 | 2003-08-24 13:42:04 | TITLE_1077302833 | IMAGE_702269538  | 2002-04-02 01:21:49 |
|  172347180 | 2003-08-21 14:26:37 | TITLE_558691044  | IMAGE_1091183587 | 2003-08-13 08:30:22 |
| 1137674509 | 2003-08-15 08:44:37 | TITLE_1982979709 | IMAGE_1234487941 | 2003-12-17 11:53:28 |
|  282998112 | 2003-08-05 10:01:34 | TITLE_353831568  | IMAGE_738487608  | 2003-11-08 22:03:22 |
|  246145344 | 2003-08-02 00:42:31 | TITLE_376954044  | IMAGE_1279375459 | 2003-12-05 02:30:49 |
|  218409162 | 2003-07-14 02:55:16 | TITLE_1932540991 | IMAGE_1078689211 | 2003-07-14 15:59:37 |
|  593263087 | 2003-07-12 22:47:01 | TITLE_1604012533 | IMAGE_834822870  | 2003-09-02 05:48:22 |
| 2115914174 | 2003-07-06 03:06:31 | TITLE_1268165545 | IMAGE_1068632322 | 2003-04-28 16:29:01 |
|  552557275 | 2003-07-01 16:45:22 | TITLE_2022112717 | IMAGE_1410588295 | 2003-11-01 01:55:16 |
| 1500437041 | 2003-06-29 20:05:19 | TITLE_35559258   | IMAGE_159953586  | 2003-08-02 10:34:07 |
| 1098371257 | 2003-06-09 07:29:37 | TITLE_1694076415 | IMAGE_1409619391 | 2004-01-07 01:00:13 |
| 1570373503 | 2003-05-22 16:45:04 | TITLE_125157894  | IMAGE_723393492  | 2003-09-26 23:22:43 |
| 1330507411 | 2003-05-05 21:40:07 | TITLE_1571250589 | IMAGE_701840418  | 2003-11-19 20:57:31 |
| 1666035620 | 2003-04-26 02:51:40 | TITLE_504713706  | IMAGE_1410357553 | 2003-11-18 01:30:04 |
| 1458179791 | 2003-04-19 05:34:25 | <NO_TITLE>       | <NO-IMAGE>       | <NO-IMAGE-DATE>     |
| 1365758305 | 2003-03-28 10:09:58 | TITLE_704554170  | IMAGE_2085080137 | 2003-11-11 16:35:19 |
| 2131082774 | 2003-03-26 16:43:25 | TITLE_1411034929 | IMAGE_303539208  | 2003-05-14 12:59:37 |
|  103396632 | 2003-02-14 09:11:28 | TITLE_915927396  | IMAGE_1381045723 | 2003-12-28 18:26:28 |
|  396479202 | 2003-02-01 15:51:40 | <NO_TITLE>       | <NO-IMAGE>       | <NO-IMAGE-DATE>     |
| 2019916250 | 2003-01-30 00:44:46 | <NO_TITLE>       | <NO-IMAGE>       | <NO-IMAGE-DATE>     |
|  431091906 | 2003-01-29 13:08:37 | <NO_TITLE>       | <NO-IMAGE>       | <NO-IMAGE-DATE>     |
|  705166549 | 2003-01-23 21:37:07 | TITLE_1530318643 | IMAGE_257673696  | 2003-08-23 19:06:22 |
| 1278327049 | 2002-12-31 16:39:40 | TITLE_772845324  | IMAGE_1355754913 | 2003-12-22 16:40:25 |
| 1871174528 | 2002-12-30 19:03:40 | TITLE_65725764   | IMAGE_522904938  | 2003-09-06 07:08:01 |
|  611892727 | 2002-12-22 10:19:07 | TITLE_333758274  | IMAGE_734815032  | 2003-09-22 19:16:43 |
|  758497849 | 2002-12-04 15:05:10 | TITLE_129140574  | IMAGE_244407066  | 2003-07-15 12:38:37 |
|  518111034 | 2002-10-17 16:38:10 | TITLE_1976498683 | IMAGE_2008599775 | 2004-01-06 16:37:34 |
| 1737725786 | 2002-10-15 23:52:52 | TITLE_1441053871 | IMAGE_1595265847 | 2003-11-24 15:23:10 |
| 1206055789 | 2002-10-03 22:07:52 | TITLE_562697952  | IMAGE_198940092  | 2003-08-23 11:56:46 |
|  702790153 | 2002-08-31 17:37:16 | TITLE_1788304903 | IMAGE_1212944101 | 2003-12-19 22:56:01 |
+------------+---------------------+------------------+------------------+---------------------+
40 rows in set (0.01 sec)

Ini kueri barunya

  SELECT
    AAA.author_id,
    AAA.date_created,
    IFNULL(BBB.title,'<NO_TITLE>') title,
    IFNULL(CCC.filename,'<NO-IMAGE>') filename,
    IFNULL(CCC.date_added,'<NO-IMAGE-DATE>') image_date
  FROM
  (
    SELECT
      AA.id,
      AA.date_added,
      BB.author_id,
      BB.date_created
    FROM
    (
      SELECT
        A.id,IFNULL(MAX(B.date_added),'1900-01-01 00:00:00') date_added
        FROM (SELECT id FROM articles ORDER BY date_created DESC LIMIT 40) A
        LEFT JOIN article_images B ON A.id = B.article_id
        GROUP BY A.id
    ) AA
    INNER JOIN articles BB USING (id)
  ) AAA
  LEFT JOIN article_contents BBB ON AAA.id=BBB.article_id
  LEFT JOIN article_images CCC
  ON (AAA.id=CCC.article_id AND AAA.date_added=CCC.date_added)
  ORDER BY AAA.date_created DESC;

Kueri saya melakukan satu hal yang tidak dilakukan kueri orang lain:

Permintaan saya mendapatkan 40 artikel terakhir terlebih dahulu sebelum bergabung ke tabel lain.

Kueri semua orang menggabungkan semuanya terlebih dahulu, lalu mencoba melakukan LIMIT 40 pada tabel sementara yang besar.

Waktu berjalan kueri saya bukan merupakan faktor jumlah data.

Terlepas dari ukuran sampel yang saya buat, kueri saya harus yang tercepat !!!



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