कम्प्युटर र सूचना प्रविधि (प्राविधिक)

कम्प्युटर र IT: प्रश्न र उत्तर

सही लागेको विकल्पमा थिच्नुहोस्। सही भए हरियो, गलत भए रातो देखिन्छ; ३ सेकेन्डपछि सही उत्तर र व्याख्या देखिन्छ।

सही: ० / ०

2071. B+ trees are preferred over B-trees for range queries mainly because in a B+ tree:

      कEach node holds only one key खAll keys are in leaf nodes, which are linked sequentially गInternal nodes store full data records घThe tree is never balanced
      💬 टिप्पणी / गल्ती रिपोर्ट (०)

      छलफल / प्रश्न उत्तरमा गल्ती छ

      पठाउनुहोस्

      टिप्पणी जाँचपछि मात्र देखिन्छ।

2072. An index in which an index entry appears for every search-key value (every record) in the data file is a:

      कDense index खClustered hash गBitmap join घSparse index
      💬 टिप्पणी / गल्ती रिपोर्ट (०)

      छलफल / प्रश्न उत्तरमा गल्ती छ

      पठाउनुहोस्

      टिप्पणी जाँचपछि मात्र देखिन्छ।

2073. In log-based recovery with immediate database modification, after a crash the system must:

      कOnly redo uncommitted transactions खOnly undo committed transactions गDelete the log and restart without recovery घRedo committed transactions and undo uncommitted ones
      💬 टिप्पणी / गल्ती रिपोर्ट (०)

      छलफल / प्रश्न उत्तरमा गल्ती छ

      पठाउनुहोस्

      टिप्पणी जाँचपछि मात्र देखिन्छ।

2074. In multiple-granularity locking, an 'IX' (intention-exclusive) lock on a table indicates that:

      कThe table is being dropped खThe whole table is locked exclusively गThe transaction intends to set exclusive locks on some rows within that table घNo other transaction may read any row of the table
      💬 टिप्पणी / गल्ती रिपोर्ट (०)

      छलफल / प्रश्न उत्तरमा गल्ती छ

      पठाउनुहोस्

      टिप्पणी जाँचपछि मात्र देखिन्छ।

2075. Optimistic concurrency control (validation-based protocol) is most suitable when:

      कTransactions are very long and always conflict खConflicts between transactions are rare गThe system has no recovery log घAlmost all transactions update the same rows
      💬 टिप्पणी / गल्ती रिपोर्ट (०)

      छलफल / प्रश्न उत्तरमा गल्ती छ

      पठाउनुहोस्

      टिप्पणी जाँचपछि मात्र देखिन्छ।

2076. In timestamp-ordering concurrency control, each transaction is given a timestamp:

      कWhen it starts, and conflicting operations are executed in timestamp order खOnly when it commits गOnly when a deadlock occurs घEqual to the number of locks it holds
      💬 टिप्पणी / गल्ती रिपोर्ट (०)

      छलफल / प्रश्न उत्तरमा गल्ती छ

      पठाउनुहोस्

      टिप्पणी जाँचपछि मात्र देखिन्छ।

2077. Under strict two-phase locking (strict 2PL):

      कA transaction may acquire locks after releasing one खAll locks are released immediately after use गLocks are never needed for reading घExclusive locks are held until the transaction commits or aborts
      💬 टिप्पणी / गल्ती रिपोर्ट (०)

      छलफल / प्रश्न उत्तरमा गल्ती छ

      पठाउनुहोस्

      टिप्पणी जाँचपछि मात्र देखिन्छ।

2078. When the failure of one transaction forces several other transactions that read its uncommitted data to roll back as well, this is called:

      कCheckpointing खLock escalation गCascading rollback घTwo-phase commit
      💬 टिप्पणी / गल्ती रिपोर्ट (०)

      छलफल / प्रश्न उत्तरमा गल्ती छ

      पठाउनुहोस्

      टिप्पणी जाँचपछि मात्र देखिन्छ।

2079. Two transactions read the same balance and then both write updated values, so that the first update is overwritten by the second. This problem is called the:

      कDirty read problem खLost update problem गPhantom problem घDeadlock problem
      💬 टिप्पणी / गल्ती रिपोर्ट (०)

      छलफल / प्रश्न उत्तरमा गल्ती छ

      पठाउनुहोस्

      टिप्पणी जाँचपछि मात्र देखिन्छ।

2080. After a transaction executes its final statement but before its changes are made permanent, it is in the:

      कPartially committed state खAborted state गActive state घFailed state
      💬 टिप्पणी / गल्ती रिपोर्ट (०)

      छलफल / प्रश्न उत्तरमा गल्ती छ

      पठाउनुहोस्

      टिप्पणी जाँचपछि मात्र देखिन्छ।