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CMPT 454 - Midterm Terms (Textbook) Exam With Complete Solutions CacheA component that stores data so future requests for that data can be served faster. Main memoryThe primary volatile storage used to store data and machine code currently being used. Flash memoryNon-volatile memory that can be electronically erased and reprogrammed. Magnetic diskA storage device that uses magnetic storage to store and retrieve digital information using one or more rigid rapidly rotating disks. Optical storageStorage of data on an optically readable medium, such as a CD, DVD, or Blu-ray disc. Tape storageA type of storage media that uses magnetic tape to store data. Volatile storageStorage that requires power to maintain the stored information. Non-volatile storageStorage that retains data even when powered off.
Sequential-accessData access method where data is read in a specific order. Direct-accessData access method where data can be read or written in any order. Serial ATA (SATA)A computer bus interface that connects host bus adapters to mass storage devices. serial advanced technology attachment (SATA)? SATA is a technology used to connectstorage devices like hard drives and solid-state drives (SSDs) to your computer'smotherboard.
Serial Attached SCSI (SAS)SCSI: Small Computer System Interface A point-to-point serial protocol that moves data to and from computer-storage devices. NVMeNon-Volatile Memory Express A high-performance, NUMA-optimized, and highly scalable storage protocol. SANStorage area network A network that provides access to consolidated block-level data storage.
Disk armThe mechanical arm that moves the read-write heads across the platters.
CylinderA collection of tracks of the same number on different platters within a disk drive.
Disk controllerThe component that manages the disk drive and mediates between the drive and the rest of the computer. ChecksumsValues used to verify the integrity of data.
Remapping of bad sectorsThe process of replacing damaged sectors with spare ones to ensure data integrity.
Disk blockThe smallest unit of data transfer between the disk drive and the CPU.
Access time
The total time it takes for a computer to retrieve data from storage. Seek timeThe time it takes for the read-write head to move to the track where data is stored.
Latency timeThe delay before data transfer begins following an instruction for its transfer.
I/O operations per second (IOPS)A common performance measurement used to benchmark computer storage devices.
Rotational latencyThe delay waiting for the rotation of the disk to bring the required disk sector under the read-write head. Data-transfer rateThe speed at which data is transferred from one location to another.
Mean time to failure (MTTF)The average time expected until the first failure of a piece of equipment.
MirroringA RAID configuration where data is copied identically to two or more drives.
Data stripingA RAID method that splits data into blocks and spreads the data blocks across multiple drives. Bit-level stripingA RAID method that splits data at the bit level across multiple drives.
Block-level stripingA RAID method that splits data at the block level across multiple drives.
RAID Level 0A RAID configuration that uses block-level striping without redundancy.
RAID Level 1A RAID configuration that uses block-level striping with mirroring.
RAID Level 5A RAID configuration that uses block-level striping with distributed parity.
RAID Level 6A RAID configuration that uses block-level striping with P + Q redundancy.
Rebuild performanceThe performance of rebuilding data on a failed drive in a RAID array.
Software RAIDRAID configurations managed by software rather than dedicated hardware.
Hardware RAIDRAID configurations managed by a dedicated hardware controller.
Hot swappingThe ability to replace or add components without stopping or shutting down the system.
Disk-arm schedulingAlgorithms to schedule disk head movements to optimize access time.
Elevator algorithm
Fixed-length recordsRecords where each field has a fixed size.
File headerThe section of a file that contains metadata about the file.
Free listA list of free or available spaces in a file or storage.
Variable-length recordsRecords where fields can vary in size.
Null bitmapA bitmap indicating which fields in a record are null.
Slotted-page structureA method of organizing records within a page.
Large objectsData types that store large amounts of data, such as BLOBs (Binary Large Objects) and CLOBs (Character Large Objects).
Heap file organizationA method of storing records in no particular order.
Sequential file organizationA method of storing records in a sequence based on a search key.
Multitable clustering file organizationA method of storing related records from multiple tables together.
B+-tree file organizationsA balanced tree data structure that maintains sorted data and allows searches, insertions, and deletions. Hashing file organizationA method of storing records that uses a hash function to determine the location of records. Free-space mapA map that tracks free space in storage.
Buffer managerThe component responsible for managing the buffer pool.
Pinned blocksBlocks in the buffer pool that are currently being used and cannot be evicted.
Evicted blocksBlocks removed from the buffer pool to make space for new blocks.
Forced output of blocksEnsuring that modified blocks are written to disk to maintain consistency.
Shared and exclusive locksLocks used to control access to data for concurrent transactions.
Least recently used (LRU)A buffer replacement strategy that evicts the block that was referenced least recently.
Toss-immediateA buffer management strategy where a block is immediately freed once it is no longer
needed. Most recently used (MRU)A buffer replacement strategy that evicts the most recently used block first.
Output of blocksThe process of writing blocks from the buffer to disk.
Journaling file systemsFile systems that keep a log of changes to ensure data integrity in case of crashes.
Column-oriented storageA storage method where data is stored column by column, which is efficient for read-heavy analytical queries. Columnar storageAnother term for column-oriented storage.
Vector processingProcessing data in columns, allowing for efficient operations on large datasets.
Indices that maintain the order of indexed values. Hash indicesIndices that use a hash function to distribute values across buckets.
Evaluation factorsCriteria for assessing indices, such as access types, access time, insertion time, deletion time, and space overhead. Access typesThe different ways an index can be used to access data.
Insertion timeThe time it takes to insert a new entry into an index.
Deletion timeThe time it takes to remove an entry from an index.
Space overheadThe additional storage space required by an index.
Ordered indexAn index that keeps its entries in a sorted order.
Clustering indexAn index where the data records themselves are sorted in the order of the search key.
Primary indicesIndices on primary keys of a table.
Nonclustering indicesIndices that are not used for ordering the data records themselves.
Secondary indicesIndices used to provide access paths for attributes that are not primary keys.
Index-sequential filesFiles that are sequentially ordered and can be accessed using an index.
Index entryAn individual entry in an index, consisting of a key and a pointer.
A balanced tree data structure that maintains sorted data and allows searches,insertions, and deletions.
Balanced treeA tree data structure where all leaf nodes are at the same level.
Leaf nodesThe bottommost nodes in a B+-tree that contain the actual data entries.
Nonleaf nodesInternal nodes in a B+-tree that guide the search path.
Internal nodesNodes in a B+-tree that are not leaf nodes, used to navigate the tree.
Range queriesQueries that retrieve data within a specified range of values.
Node splitThe process of dividing a node into two when it becomes too full.
Node coalesceThe process of merging nodes when they become too empty.
Redistribute of pointersAdjusting pointers when nodes are split or coalesced.
UniquifierA unique identifier used in B+-trees to distinguish between duplicate keys.
Prefix compressionA method of reducing the size of index entries by storing common prefixes only once.
Bulk loadingEfficiently loading large amounts of data into a B+-tree index.
Bottom-up B+-tree constructionBuilding a B+-tree from the leaf nodes up to the root.
B-tree indicesA type of balanced tree data structure similar to B+-trees but with some differences in
