Ib tus cursor implicit muaj tus cwj pwm uas rov qab cov ntaub ntawv hais txog qhov nyuam qhuav khiav SELECT lossis DML nqe lus uas tsis cuam tshuam nrog tus cursor lub npe. … Koj tuaj yeem siv tus cursor tus cwj pwm nkaus xwb hauv cov lus qhia, tsis yog hauv SQL nqe lus.
Yuav ua li cas 3 ntawm cov hauv qab no yog tus cursor implicit?
Tus cursor tshiab kawg yog hu ua SQL cursor thiab muaj cov yam ntxwv zoo li % FOUND, %ISOPEN, %NOTFOUND, thiab %ROWCOUNT.
Puas yog Rowcount tus cursor implicit?
PL/SQL tshaj tawm a cursor implicitly rau tag nrho SQL cov ntaub ntawv manipulation nqe lus … Tus nqi ntawm SQL%ROWCOUNT tus cwj pwm yog hais txog cov lus tshaj tawm tsis ntev los no los ntawm PL/SQL. Thaum nws tus cursor lossis tus cursor hloov pauv tau qhib, %ROWCOUNT yog xoom.
Yuav ua li cas yog cursor attributes?
Txhua tus cursor qhia meej thiab tus cursor sib txawv muaj plaub yam: % FOUND, %ISOPEN %NOTFOUND, thiab %ROWCOUNT. Thaum ntxiv rau tus cursor lossis tus cursor hloov pauv, cov cwj pwm no rov qab cov ntaub ntawv tseem ceeb ntawm kev ua tiav ntawm cov ntaub ntawv tswj xyuas.
Qhov twg hauv qab no tsis yog tus cursor yam ntxwv?
Qhov twg hauv qab no tsis yog tus cursor yam ntxwv?
- % pom.
- %notfound.
- %rowcount.
- %rowtype.
