sql >> Databasteknik >  >> RDS >> Mysql

MySQL-operator VÄLJ hur man får ett exakt radresultat från liknande rader?

create table stuff
(   id int auto_increment primary key,
    seo varchar(100) not null
    -- unique key (seo) not a bad idea
);

insert stuff (seo) values ('abc'),('abc7'),('kitty likes abc'),('abc and more abc'),('kittens');
insert stuff (seo) values ('abc at beginning'),('frogs'),('and at the end abc'),('qwertyabcqwerty');


select id from stuff where seo='abc';
+----+
| id |
+----+
|  1 |
+----+
1 row in set (0.02 sec)

Så här like beter sig:

select * from stuff where seo like '%abc';
+----+--------------------+
| id | seo                |
+----+--------------------+
|  1 | abc                |
|  3 | kitty likes abc    |
|  4 | abc and more abc   |
|  8 | and at the end abc |
+----+--------------------+
4 rows in set (0.00 sec)

select * from stuff where seo like 'abc%';
+----+------------------+
| id | seo              |
+----+------------------+
|  1 | abc              |
|  2 | abc7             |
|  4 | abc and more abc |
|  6 | abc at beginning |
+----+------------------+
4 rows in set (0.00 sec)

select id,seo from stuff where seo like '%abc%';
+----+--------------------+
| id | seo                |
+----+--------------------+
|  1 | abc                |
|  2 | abc7               |
|  3 | kitty likes abc    |
|  4 | abc and more abc   |
|  6 | abc at beginning   |
|  8 | and at the end abc |
|  9 | qwertyabcqwerty    |
+----+--------------------+
7 rows in set (0.00 sec)


  1. FEL 1067 (42000):Ogiltigt standardvärde för 'sluttid'

  2. Hur använder man Timestamp_to_scn och Scn_to_timestamp i Oracle?

  3. Hur man skapar Not Null-begränsning på kolumn i SQL Server-tabell - SQL Server / T-SQL självstudie del 51

  4. Vad är PostgreSQL-motsvarigheten till SYSDATE från Oracle?