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Operator `~` (tilde) dalam Pencarian Teks Lengkap Boolean di MySQL tidak berperilaku seperti yang dinyatakan di situs web pengembang MySQL

Meskipun tidak ada dokumentasi mengenai jawaban saya di mana pun, setelah eksperimen menyeluruh saya sampai pada kesimpulan paling logis ini -

Keberadaan operator '+' meniadakan efek apa pun dari operator '~'

Saya telah memperbarui tabel fruits dengan nilai berikut -

SELECT * FROM fruits;
+----+-------------------------+
| id | name                    |
+----+-------------------------+
|  1 | apple orange watermelon |
|  2 | apple mango pomegranate |
|  3 | apple mango banana      |
|  4 | mango kiwi pomegranate  |
|  5 | mango guava watermelon  |
|  6 | apple banana kiwi       |
+----+-------------------------+

Pertanyaan 1:

SELECT id, name FROM fruits
    -> WHERE MATCH(name) AGAINST
    -> ('apple mango ~pomegranate'
    -> IN BOOLEAN MODE);
+----+-------------------------+
| id | name                    |
+----+-------------------------+
|  3 | apple mango banana      |
|  1 | apple orange watermelon |
|  5 | mango guava watermelon  |
|  6 | apple banana kiwi       |
|  2 | apple mango pomegranate |
|  4 | mango kiwi pomegranate  |
+----+-------------------------+

Pertanyaan 2:

SELECT id, name FROM fruits
    -> WHERE MATCH(name) AGAINST
    -> ('apple ~pomegranate'
    -> IN BOOLEAN MODE);
+----+-------------------------+
| id | name                    |
+----+-------------------------+
|  1 | apple orange watermelon |
|  3 | apple mango banana      |
|  6 | apple banana kiwi       |
|  2 | apple mango pomegranate |
+----+-------------------------+

Pertanyaan 3:

SELECT id, name FROM fruits
    -> WHERE MATCH(name) AGAINST
    -> ('mango ~pomegranate'
    -> IN BOOLEAN MODE);
+----+-------------------------+
| id | name                    |
+----+-------------------------+
|  3 | apple mango banana      |
|  5 | mango guava watermelon  |
|  2 | apple mango pomegranate |
|  4 | mango kiwi pomegranate  |
+----+-------------------------+

Di sini, dalam kueri 1, 2 &3 tidak ada operator yang mendahului nilai apple dan mango dan ~ operator mendahului nilai pomegranate . Ini memastikan bahwa baris memiliki kata pomegranate berperingkat lebih rendah dari yang lain.

Pertanyaan 4:

SELECT id, name FROM fruits
    -> WHERE MATCH(name) AGAINST
    -> ('+apple +mango ~pomegranate'
    -> IN BOOLEAN MODE);
+----+-------------------------+
| id | name                    |
+----+-------------------------+
|  2 | apple mango pomegranate |
|  3 | apple mango banana      |
+----+-------------------------+

Pertanyaan 5:

SELECT id, name FROM fruits
    -> WHERE MATCH(name) AGAINST
    -> ('+apple ~pomegranate'
    -> IN BOOLEAN MODE);
+----+-------------------------+
| id | name                    |
+----+-------------------------+
|  1 | apple orange watermelon |
|  2 | apple mango pomegranate |
|  3 | apple mango banana      |
|  6 | apple banana kiwi       |
+----+-------------------------+

Pertanyaan 6:

SELECT id, name FROM fruits
    -> WHERE MATCH(name) AGAINST
    -> ('+mango ~pomegranate'
    -> IN BOOLEAN MODE);
+----+-------------------------+
| id | name                    |
+----+-------------------------+
|  2 | apple mango pomegranate |
|  3 | apple mango banana      |
|  4 | mango kiwi pomegranate  |
|  5 | mango guava watermelon  |
+----+-------------------------+

Di sini, dalam kueri 4, 5 &6 + operator mendahului nilai apple dan mango dan ~ operator mendahului nilai pomegranate . Jelas kehadiran + operator membatalkan semua efek ~ operator.

Pertanyaan 7:

SELECT id, name FROM fruits
    -> WHERE MATCH(name) AGAINST
    -> ('+apple +mango <pomegranate'
    -> IN BOOLEAN MODE);
+----+-------------------------+
| id | name                    |
+----+-------------------------+
|  3 | apple mango banana      |
|  2 | apple mango pomegranate |
+----+-------------------------+

Kueri 8:

SELECT id, name FROM fruits
    -> WHERE MATCH(name) AGAINST
    -> ('+apple <pomegranate'
    -> IN BOOLEAN MODE);
+----+-------------------------+
| id | name                    |
+----+-------------------------+
|  1 | apple orange watermelon |
|  3 | apple mango banana      |
|  6 | apple banana kiwi       |
|  2 | apple mango pomegranate |
+----+-------------------------+

Pertanyaan 9:

SELECT id, name FROM fruits
    -> WHERE MATCH(name) AGAINST
    -> ('+mango <pomegranate'
    -> IN BOOLEAN MODE);
+----+-------------------------+
| id | name                    |
+----+-------------------------+
|  3 | apple mango banana      |
|  5 | mango guava watermelon  |
|  2 | apple mango pomegranate |
|  4 | mango kiwi pomegranate  |
+----+-------------------------+

Di sini, dalam kueri 7, 8 &9 + operator mendahului nilai apple dan mango dan < operator mendahului nilai pomegranate . Ini memastikan bahwa baris memiliki kata pomegranate berperingkat lebih rendah dari yang lain.

Jadi, yang dapat disimpulkan dari sini adalah bahwa -if + operator ada, gunakan < operator alih-alih ~ operator

PERBARUI

Setelah perhitungan ekstensif, saya telah membuat tabel fruits_score_count yang menunjukkan score dari setiap fruits setelah selesai mencari Boolean FULLTEXT.

SELECT * FROM fruits_score_count;
+----+-------------+---------------------+----------------------+
| id | fruit_name  | row_numbers_matched | score                |
+----+-------------+---------------------+----------------------+
|  1 | apple       |                   4 | 0.031008131802082062 |
|  2 | banana      |                   2 |  0.22764469683170319 |
|  3 | guava       |                   1 |   0.6055193543434143 |
|  4 | kiwi        |                   2 |  0.22764469683170319 |
|  5 | mango       |                   4 | 0.031008131802082062 |
|  6 | orange      |                   1 |   0.6055193543434143 |
|  7 | pomegranate |                   2 |  0.22764469683170319 |
|  8 | watermelon  |                   2 |  0.22764469683170319 |
+----+-------------+---------------------+----------------------+

Pertanyaan 1:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('apple mango ~pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  3 | apple mango banana      | 0.062016263604164124 |
|  1 | apple orange watermelon | 0.031008131802082062 |
|  5 | mango guava watermelon  | 0.031008131802082062 |
|  6 | apple banana kiwi       | 0.031008131802082062 |
|  2 | apple mango pomegranate |  -0.7103390693664551 |
|  4 | mango kiwi pomegranate  |  -0.7413471937179565 |
+----+-------------------------+----------------------+

Pertanyaan 2:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('apple ~pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  1 | apple orange watermelon | 0.031008131802082062 |
|  3 | apple mango banana      | 0.031008131802082062 |
|  6 | apple banana kiwi       | 0.031008131802082062 |
|  2 | apple mango pomegranate |  -0.7413471937179565 |
+----+-------------------------+----------------------+

Pertanyaan 3:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('mango ~pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  3 | apple mango banana      | 0.031008131802082062 |
|  5 | mango guava watermelon  | 0.031008131802082062 |
|  2 | apple mango pomegranate |  -0.7413471937179565 |
|  4 | mango kiwi pomegranate  |  -0.7413471937179565 |
+----+-------------------------+----------------------+

Pertanyaan 4:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('+apple +mango ~pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  2 | apple mango pomegranate | 0.062016263604164124 |
|  3 | apple mango banana      | 0.062016263604164124 |
+----+-------------------------+----------------------+

Pertanyaan 5:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('+apple ~pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  1 | apple orange watermelon | 0.031008131802082062 |
|  2 | apple mango pomegranate | 0.031008131802082062 |
|  3 | apple mango banana      | 0.031008131802082062 |
|  6 | apple banana kiwi       | 0.031008131802082062 |
+----+-------------------------+----------------------+

Pertanyaan 6:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('+mango ~pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  2 | apple mango pomegranate | 0.031008131802082062 |
|  3 | apple mango banana      | 0.031008131802082062 |
|  4 | mango kiwi pomegranate  | 0.031008131802082062 |
|  5 | mango guava watermelon  | 0.031008131802082062 |
+----+-------------------------+----------------------+

Pertanyaan 7:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('+apple +mango <pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  3 | apple mango banana      | 0.062016263604164124 |
|  2 | apple mango pomegranate |  -0.7103390693664551 |
+----+-------------------------+----------------------+

Kueri 8:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('+apple <pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  1 | apple orange watermelon | 0.031008131802082062 |
|  3 | apple mango banana      | 0.031008131802082062 |
|  6 | apple banana kiwi       | 0.031008131802082062 |
|  2 | apple mango pomegranate |  -0.7413471937179565 |
+----+-------------------------+----------------------+

Pertanyaan 9:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('+mango <pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  3 | apple mango banana      | 0.031008131802082062 |
|  5 | mango guava watermelon  | 0.031008131802082062 |
|  2 | apple mango pomegranate |  -0.7413471937179565 |
|  4 | mango kiwi pomegranate  |  -0.7413471937179565 |
+----+-------------------------+----------------------+

Di sini, Kueri 1, Kueri 2, Kueri 3, Kueri 7, Kueri 8, Kueri 9 berperilaku seperti yang diharapkan.

Tapi dari Query 4, Query 5, Query 6 jelas bahwa -

Di hadapan + operator sebelum nilai dengan ~ operator pada dasarnya membuat nilai tidak terlihat.

Pengamatan yang cermat juga mengungkapkan bahwa -

x ~y dan +x <y setara

Eksperimentasi LEBIH LANJUT

Pertanyaan 1:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('+mango apple ~pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  3 | apple mango banana      | 0.062016263604164124 |
|  4 | mango kiwi pomegranate  | 0.031008131802082062 |
|  5 | mango guava watermelon  | 0.031008131802082062 |
|  2 | apple mango pomegranate |  -0.7103390693664551 |
+----+-------------------------+----------------------+
  • Baris 1 dengan id = 3 mendapat skor maksimum yang merupakan jumlah skor mango dan apple .
  • Baris 2 dengan id = 4 mendapat skor maksimum kedua yaitu skor mango . Adanya + operator di depan mango membuat ~pomegranate frase pencarian tidak relevan.
  • Baris 3 dengan id = 5 mendapat skor yang sama dengan Baris 2. Tetapi ditempatkan lebih rendah dari Baris 2 karena ketika skornya sama, baris diberi peringkat dalam urutan primary key yang meningkat , di sini id adalah primary key .
  • Baris 4 dengan id = 2 mendapat skor terendah dan karenanya datang terakhir. Di sini sejak kata apple hadir dan dalam frasa pencarian tidak ada + operator sebelum apple , maka ~pomegranate dalam frasa penelusuran dipertimbangkan, yang menurunkan skor secara signifikan.

Pertanyaan 2:

SELECT id, name, score FROM
    -> (SELECT id, name, MATCH(name) AGAINST
    -> ('+mango apple <pomegranate' IN BOOLEAN MODE)
    -> AS score FROM fruits ORDER BY score DESC)
    -> AS temp WHERE score != 0;
+----+-------------------------+----------------------+
| id | name                    | score                |
+----+-------------------------+----------------------+
|  3 | apple mango banana      | 0.062016263604164124 |
|  5 | mango guava watermelon  | 0.031008131802082062 |
|  2 | apple mango pomegranate |  -0.7103390693664551 |
|  4 | mango kiwi pomegranate  |  -0.7413471937179565 |
+----+-------------------------+----------------------+

Ini sekali lagi menggambarkan bahwa < operator berlaku bahkan dengan adanya + operator.

Ini semakin memperkuat pengamatan saya sebelumnya bahwa -

jika + operator hadir, gunakan < operator alih-alih ~ operator




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