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More SQL and Application Programming
Disk
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구조
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Access Time = seek time + rotational delay + transfer time + other
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Speeding up disk access
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organize data by cylinder
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use multiple disks
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mirror disk
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disk scheduling
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double buffering
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Disk failures
File System Structure
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Fixed length
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packing
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Addressing
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Logical → Physical address
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Physical → memory address
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offset table & structured scheme
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Variable length
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variable size of data
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repeating → 2가지 방법
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insertion & deletion
Indexing and Hasing
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Index
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Dense
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Sparse
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Multiple Level
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Secondary Index
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Inverted Index
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B-Tree
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구조
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Look up
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Insertion
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Deletion
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Duplicated keys
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Efficiency
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Hash Table
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Static & efficiency
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Extensible
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Linear Hashing
Query Processing
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Parse Query
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Select logical query plan
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select physical query plan
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Query execution
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Logical plan selection
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Commutative and associative laws
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Laws for selection
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Laws for projection
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Laws about join and products
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Laws for duplicate elimination
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Laws for grouping and aggregation
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Which transformation is good?
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Physical plan selection
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Estimate size of result
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Size Parameter
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Estimating projection
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Estimating selection
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Estimating join
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Estimating Union, Intersect, difference, duplicate elimination, grouping
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Obtating estimate for size parameter
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Estimate the number of disk I/O’s
Crash Recovery
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Transaction
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Undo logging
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Redo logging
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Undo/Redo logging
Concurrency Control
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Seiral Schedule
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Serializable schedule
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Conflict & Conflic-serializable schedule
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Precedence graph
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Locking
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Two-phase Locking
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deadlocks
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several mode
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update lock
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increment lock
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locking schedule
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lock table
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warning lock
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Tree based locking & Tree protocol
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Optimistic locking
More Transaction Manager
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Concurrency control & recovery
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Deadlocks
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Detection
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Prevention
MapReduce
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NoSQL
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MapReduce/Hadoop
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Apache Spark
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NewSQL