Kodi MySQL imapanga bwanji zotsatizana? MySQL database yopanga auto-increment sequence statement

MySQLKodi kupanga ndandanda?MySQL databasePangani mawu otsatizana odziwonjezera okha

Kugwiritsa ntchito kwa MySQL

Mndandanda wa MySQL ndi mndandanda wazinthu zambiri: 1, 2, 3, ..., popeza tebulo la deta likhoza kukhala ndi kiyi imodzi yokha yowonjezera yowonjezera, ngati mukufuna kukwaniritsa kuwonjezereka kwa magawo ena, mungagwiritse ntchito MySQL kutsatizana. kukwaniritsa.

M'mutu uno tifotokoza momwe tingagwiritsire ntchito mndandanda wa MySQL.

Gwiritsani ntchito AUTO_INCREMENT

Njira yosavuta yogwiritsira ntchito zotsatizana mu MySQL ndikugwiritsa ntchito MySQL AUTO_INCREMENT kutanthauzira mizati.

Chitsanzo

Deta ya data Insect imapangidwa mu chitsanzo chotsatirachi, chomwe palibe phindu lomwe limatchulidwa kuti likule.

mysql > CREATE TABLE昆虫
     - > （- > id INT UNSIGNED NOT NULL AUTO_INCREMENT ，- > PRIMARY KEY （id ），- > name VARCHAR （30 ）NOT NULL ，＃昆虫类型- > 日期DATE NOT NULL ，＃收集日期- > origin VARCHAR （30 ）NOT NULL ＃where collected ）; 查询OK ，0 行受影响（0.02 秒）
mysql > 
    
    
     
     
    

 INSERT INTO insects （id ，name ，date ，origin ）VALUES
     - > （NULL ，'housefly' ，'2001-09-10' ，'kitchen' ），- > （NULL ，'millipede' ，'2001-09-10 ' ，'车道' ），- > （NULL ，'grasshopper' ，'2001-09-10' ，'front yard' ）; 查询OK ， 
     
     
 秒）记录：3 重复：0 警告：0 
mysql > 选择* 从昆虫ORDER BY ID ; + ---- + ------------- + ------------ + ------------ + | id | 名字         | 日期        | 起源      | + ---- + ------------- + ------------ + ------------ + | 1 | 家蝇     | 2001 - 09 - 10 | 厨房     | | 2 | 千足虫   
       



     
   | 2001 - 09 - 10 | 车道    | | 3 | 蚱蜢| 2001 - 09 - 10 | 前院| + ---- + ------------- + ------------ + ------------ + 3 行中集（0.00 秒）  
     

  

Pezani mtengo wa AUTO_INCREMENT

Mu kasitomala wa MySQL mutha kugwiritsa ntchito LAST_INSERT_ID() ntchito mu SQL kuti mupeze mtengo wagawo lomaliza lowonjezera lokha loyikidwa patebulo.

Ntchito zofananira zimaperekedwanso mu PHP kapena PERL script kuti mupeze mtengo wagawo lowonjezera-lomwe layikidwa patebulo lomaliza.

Chitsanzo cha PERL

Gwiritsani ntchito mysql_insertid katundu kuti mupeze mtengo wa AUTO_INCREMENT.Zitsanzo ndi izi:

$ dbh - > do （“INSERT INTO insect（name，date，origin） 
VALUES（'moth'，'2001-09-14'，'windowsill'）“ ）; my $ seq = $ dbh - > { mysql_insertid };

PHP chitsanzo

PHP imapeza mtengo wa gawo la AUTO_INCREMENT muzolemba za SQL zomwe zachitika kudzera mu mysql_insert_id() ntchito.

mysql_query （“INSERT INTO昆虫（名字，日期，起源）
VALUES（'moth'，'2001-09-14'，'windowsill'）“ ，$ conn_id ）; 
$ seq = mysql_insert_id （$ conn_id ）;

sinthaninso kutsata

Mukachotsa ma rekodi angapo patebulo la data ndipo mukufuna kusinthanso gawo la AUTO_INCREMENT la data yotsalayo, mutha kutero pochotsa gawo lodziwonjezera lokha ndikuwonjezeranso.Komabe, opaleshoniyi iyenera kukhala yosamala kwambiri, ngati ayi.Nthawi yomweyo yochotsa, zolemba zatsopano zimawonjezedwa, ndipo pakhoza kukhala chisokonezo cha data.

mysql > ALTER TABLE昆虫DROP ID ; 
mysql > ALTER TABLE昆虫
     - > ADD ID INT UNSIGNED NOT NULL AUTO_INCREMENT FIRST ，- > ADD PRIMARY KEY （id ）;
    

Khazikitsani mtengo woyambira wotsatizana

Kawirikawiri, mtengo woyambira wa ndondomekoyi ndi 1, koma ngati mukufuna kufotokoza mtengo woyambira wa 100, ndiye kuti tikhoza kuchita ndi mawu awa:

mysql > CREATE TABLE昆虫
     - > （- > id INT UNSIGNED NOT NULL AUTO_INCREMENT ，- > PRIMARY KEY （id ），- > name VARCHAR （30 ）NOT NULL ，- > date DATE NOT NULL ，- > origin VARCHAR （30 ）NOT NULL
 ）engine = innodb auto_increment = 100 charset = utf8 ; 
    
    
     
    
    

Kapena mutha kugwiritsanso ntchito mawu otsatirawa tebulo litapangidwa bwino:

mysql > ALTER TABLE t AUTO_INCREMENT = 100 ;