MySQL'de karakter setleri ve kar\u015f\u0131la\u015ft\u0131rma kurallar\u0131, veritaban\u0131nda metin verilerinin nas\u0131l saklanaca\u011f\u0131n\u0131 ve nas\u0131l kar\u015f\u0131la\u015ft\u0131r\u0131laca\u011f\u0131n\u0131 belirler. Bu yaz\u0131da, MySQL'de karakter setleri ve kar\u015f\u0131la\u015ft\u0131rma kurallar\u0131n\u0131n nas\u0131l kullan\u0131laca\u011f\u0131n\u0131, tablo ve s\u00fctun d\u00fczeyinde nas\u0131l ayarlanaca\u011f\u0131n\u0131 ele alaca\u011f\u0131z.<\/p>
#### 1. Hangi Karakter Seti ve Kar\u015f\u0131la\u015ft\u0131rma Kural\u0131 Kullan\u0131lmal\u0131?<\/p>
MySQL'de onlarca karakter seti ve y\u00fczlerce kar\u015f\u0131la\u015ft\u0131rma kural\u0131 bulunur. Ancak genellikle sadece birka\u00e7 karakter seti \u00f6nemlidir:<\/p>
- **ascii**: Temel 7-bit karakterler.
- **latin1**: ASCII art\u0131 Bat\u0131 Avrupa dilleri i\u00e7in gerekli karakterler.
- **utf8**: 1, 2 ve 3 byte'l\u0131k UTF-8 karakterlerini i\u00e7erir. Emoji ve baz\u0131 \u00c7ince karakterleri i\u00e7ermez.
- **utf8mb4**: T\u00fcm UTF-8 karakterlerini i\u00e7erir ve t\u00fcm dilleri destekler.<\/p>
**En iyi uygulama:**<\/p>
- Metin veya `VARCHAR` s\u00fctunlar\u0131 i\u00e7in `utf8mb4` kullan\u0131n.
- Hex string'ler (UUID, MD5, vb.) ve basit kodlar (\u00fclke kodu, posta kodu, vb.) i\u00e7in `ascii` veya `latin1` kullan\u0131n.<\/p>
#### 2. Tablo ve S\u00fctun D\u00fczeyinde Karakter Seti Ayarlama<\/p>
Karakter setleri, hem tablo hem de s\u00fctun d\u00fczeyinde ayarlanabilir. A\u015fa\u011f\u0131daki \u00f6rnekte, `Address` tablosu i\u00e7in karakter seti ve s\u00fctun d\u00fczeyinde ayarlamalar g\u00f6sterilmi\u015ftir:<\/p>
```sql
CREATE TABLE Address (
AddressID INTEGER NOT NULL PRIMARY KEY,
Street VARCHAR(80) CHARACTER SET ASCII,
City VARCHAR(80),
Country VARCHAR(80) DEFAULT \"United States\",
Active BOOLEAN DEFAULT 1
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
```<\/p>
- **Street**: ASCII karakter seti kullan\u0131r.
- **City** ve **Country**: Tablonun varsay\u0131lan karakter seti olan `utf8mb4` kullan\u0131r.<\/p>
#### 3. Ba\u011flant\u0131 D\u00fczeyinde Karakter Seti Ayarlama<\/p>
MySQL sunucusuna, istemcinin kulland\u0131\u011f\u0131 karakter kodlamas\u0131n\u0131 belirtmek \u00f6nemlidir. Bu, `SET NAMES` komutu ile yap\u0131l\u0131r:<\/p>
```sql
SET NAMES utf8mb4;
```<\/p>
Bu komut, istemcinin `utf8mb4` karakter setini kulland\u0131\u011f\u0131n\u0131 MySQL sunucusuna bildirir. Bu, \u00f6zellikle farkl\u0131 karakter setleri kullan\u0131ld\u0131\u011f\u0131nda veri d\u00f6n\u00fc\u015f\u00fcmlerini otomatik olarak y\u00f6netir.<\/p>
#### 4. MyISAM'dan InnoDB'ye D\u00f6n\u00fc\u015ft\u00fcrme<\/p>
MyISAM ve InnoDB, MySQL'in iki farkl\u0131 depolama motorudur. InnoDB, i\u015flem deste\u011fi ve daha iyi performans sa\u011flar. MyISAM tablolar\u0131n\u0131 InnoDB'ye d\u00f6n\u00fc\u015ft\u00fcrmek i\u00e7in a\u015fa\u011f\u0131daki komut kullan\u0131l\u0131r:<\/p>
##### \u00d6rnek: Temel D\u00f6n\u00fc\u015ft\u00fcrme<\/p>
```sql
ALTER TABLE foo ENGINE=InnoDB;
```<\/p>
Bu komut, `foo` tablosunu MyISAM'den InnoDB'ye d\u00f6n\u00fc\u015ft\u00fcr\u00fcr.<\/p>
##### \u00d6rnek: Bir Veritaban\u0131ndaki T\u00fcm Tablolar\u0131 D\u00f6n\u00fc\u015ft\u00fcrme<\/p>
Bir veritaban\u0131ndaki t\u00fcm MyISAM tablolar\u0131n\u0131 InnoDB'ye d\u00f6n\u00fc\u015ft\u00fcrmek i\u00e7in a\u015fa\u011f\u0131daki SQL sorgusu kullan\u0131l\u0131r:<\/p>
```sql
SET @DB_NAME = DATABASE();<\/p>
SELECT CONCAT('ALTER TABLE `', table_name, '` ENGINE=InnoDB;') AS sql_statements
FROM information_schema.tables
WHERE table_schema = @DB_NAME
AND ENGINE = 'MyISAM'
AND TABLE_TYPE = 'BASE TABLE';
```<\/p>
Bu sorgu, veritaban\u0131ndaki t\u00fcm MyISAM tablolar\u0131n\u0131 InnoDB'ye d\u00f6n\u00fc\u015ft\u00fcrmek i\u00e7in gerekli `ALTER TABLE` komutlar\u0131n\u0131 \u00fcretir. Bu komutlar\u0131 kopyalay\u0131p \u00e7al\u0131\u015ft\u0131rabilirsiniz.<\/p>
#### Sonu\u00e7<\/p>
MySQL'de karakter setleri ve kar\u015f\u0131la\u015ft\u0131rma kurallar\u0131, veritaban\u0131nda metin verilerinin do\u011fru \u015fekilde saklanmas\u0131n\u0131 ve kar\u015f\u0131la\u015ft\u0131r\u0131lmas\u0131n\u0131 sa\u011flar. `utf8mb4`, modern uygulamalar i\u00e7in en iyi se\u00e7enektir. Ayr\u0131ca, MyISAM tablolar\u0131n\u0131 InnoDB'ye d\u00f6n\u00fc\u015ft\u00fcrmek, i\u015flem deste\u011fi ve performans avantajlar\u0131 sa\u011flar. Bir sonraki yaz\u0131da g\u00f6r\u00fc\u015fmek \u00fczere!<\/p>","excerpt":"MySQL'de karakter setleri ve kar\u015f\u0131la\u015ft\u0131rma kurallar\u0131, veritaban\u0131nda metin verilerinin do\u011fru \u015fekilde saklanmas\u0131n\u0131 ve kar\u015f\u0131la\u015ft\u0131r\u0131lmas\u0131n\u0131 sa\u011flar. `utf8mb4`, modern uygulamalar i\u00e7in en iyi se\u00e7enektir. Ayr\u0131ca, MyISAM tablolar\u0131n\u0131 InnoDB'ye d\u00f6n\u00fc\u015ft\u00fcrmek, i\u015flem deste\u011fi ve performans avantajlar\u0131 sa\u011flar.","created_at":"2025-01-13 15:38:12","updated_at":"2026-09-07 00:55:33","category_id":9,"view_count":697,"reading_time":3,"status":"published","editor_choice":0,"is_editor_choice":0,"published_at":"2025-01-13 15:38:12","featured_image":"resimyok.jpg","slug":"sql-notlari-karakter-setleri-ve-karsilastirma-kurallari-collations","category_name":"Yaz\u0131l\u0131m","category_slug":"yazilim"}