Distributed Query Processing 편집하기 (부분)

==Steps in Distributed Query Processing==
Distributed query processing typically involves the following steps:
#'''Query Parsing:'''
#*The query is analyzed and validated for syntax and semantics.
#*The query is transformed into an internal representation such as a query tree or directed acyclic graph (DAG).
#'''Query Decomposition:'''
#*The high-level query is decomposed into smaller sub-queries that can be executed on different nodes.
#*Logical query operators (e.g., selection, projection, join) are applied.
#'''Data Localization:'''
#*Identifies the nodes that store the required data for each sub-query.
#'''Query Optimization:'''
#*Determines the most efficient execution plan by minimizing communication costs, data transfer, and computation time.
#*Optimization techniques include cost-based optimization, heuristics, and rule-based strategies.
#'''Query Execution:'''
#*Executes the sub-queries on the respective nodes.
#*Combines the results from sub-queries to generate the final output.