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Sida Loo Qoro Hawlaha Daaqadda SQL ee AI Quiz

Hubi qaybaha daaqadaha SQL, kala saraynta isku xidhka iyo wadarta guud ee jaantusyada wax iibsiga, taariikhaha maqan iyo doorashada dhacdadii ugu dambaysay.

Wadooyinka haga ee la xidhiidhaShaqooyinka Daaqadda Sql ee AI
Su'aal 1 ee 8

Iibka la dalbaday ee 5, 7 iyo 4, keebaa wadarta orodka saf-ilaa ee u dhigma qaabka hagaha?

Horudhac su'aal kasta8 su'aalo

Jawaabaha iyo sharraxaadaha waxay soo baxayaan markaad qaadanayso kediska.

  1. Iibka la dalbaday ee 5, 7 iyo 4, keebaa wadarta orodka saf-ilaa ee u dhigma qaabka hagaha?
    • 5, 7 and 4
    • 5, 12 and 16
    • 16, 16 and 16
    • 5, 14 and 12
  2. Hoos u dhaca dhibcaha 100, 100 iyo 90, waa kuwee isku xigxiga RANK soo saaro?
    • 1, 2 and 3
    • 1, 1 and 2
    • 2, 2 and 3
    • 1, 1 and 3
  3. Shaqadee ayaa siinaysa dhibcaha 100, 100 iyo 90 ee darajooyinka 1, 1 iyo 2?
    • DENSE_RANK
    • ROW_NUMBER
    • RANK
    • LAG
  4. Weydiinta dhacdadii u dambaysay waxay isticmaashaa ROW_NUMBER lagu dalbaday oo keliya shaambad ay wadaagaan laba dhacdo. Maxaa loo baahan yahay doorasho la saadaalin karo oo dhexdooda ah?
    • Remove the account partition
    • Replace the final result with an unqualified DISTINCT
    • Add an appropriate tie-breaker to the window ordering
    • Assume insertion order resolves every tie
  5. Waa maxay sababta LAG ee iibka maalinlaha ah ugu guuldareysto inuu matalo iibkii shalay?
    • LAG always refers to the first row of the entire table
    • The previous recorded row may be separated by missing dates
    • LAG automatically groups all dates in one month
    • The function replaces missing dates with zero
  6. An ORDER BY appears inside OVER. What is still needed if the final displayed result must have a specified order?
    • Only a PARTITION BY with the same column
    • Only a ROWS frame using the same ordering column
    • No further clause because window ordering guarantees display order
    • A final ORDER BY for the query result
  7. Why should a tie-breaker not be added indiscriminately to RANK when equal scores should share a rank?
    • It can change which rows are peers and therefore change tied ranks
    • It leaves peer membership unchanged because only the first ordering column matters
    • It changes only the final display order and never the window calculation
    • It preserves equal-score ranks while automatically making their row numbers predictable
  8. In PostgreSQL, how can a query filter rows using a window value calculated in an inner SELECT?
    • Use that value in the same SELECT's WHERE without another query level
    • Replace OVER with GROUP BY in every case
    • Filter in an outer query or common table expression
    • Assume every database supports an identical QUALIFY clause