Introduction to Key | Primary key, Candidate key, Alternative Key and Composite Key in SInhala| ICT

[@kawithapivithuru6542]

Niyamai sir,,pehedily hodata

[@valefarx]

Thank you sir lub u ❤

[@UR-Cristiano-Ronaldo-w2b]

❤

[@SinuraVinudhiWahalathanthri]

Sir if they ask what is the primary key of relation with identical rows but in one column there is another value how do we answer it?

[@DS-IT-ACADEMY]

Question is little confusing .
Pk always, unique n not null. You can have one or more attributes as PK.

[@SinuraVinudhiWahalathanthri]

@@DS-IT-ACADEMY Thank you so much sir for replying.

[@Dimuthu_K]

sir e kiyanne eka column ekak primary key eka widiyata ganna bari unahama(data repeat wenawanam) neda composite key ekak daanne??

[@DS-IT-ACADEMY]

oww. Primary key ekk aniwarn unique wenna ona

[@Infinity-og3jp]

🤟

[@vinuthicosta993]

is the foreign key and the alternate key are both same?

[@DS-IT-ACADEMY]

Noo two different things

[@wasanaaberathne3830]

No please watch again this vedio

[@sandarudahanayake5804]

what is super key

[@NipuliRandima]

Candidate keys

[@don_naven]

foreign key ?

[@DS-IT-ACADEMY]

Discussed with db constraints

[@shasikasampath8628]

Sir..composite key ekei compound key ekei wenasa mokkd?

[@DS-IT-ACADEMY]

Dekama ekaa....

[@saumyasathsaranirathnayake2341]

Then, sir, what is the Partial Key?

[@DS-IT-ACADEMY]

All the records cannot be identified uniquely using a partial key. Only some of records

[@saumyasathsaranirathnayake2341]

@@DS-IT-ACADEMY Thank you so much Sir.