What is query processing in distributed database?
Table of Contents
What is query processing in distributed database?
Distributed query processing is the procedure of answering queries (which means mainly read operations on large data sets) in a distributed environment where data is managed at multiple sites in a computer network.
What are the 4 main phases of query processing?
➢ Four main Phases: decomposition, optimization, code generation and execution.
What is query processing steps?
Query Processing is the activity performed in extracting data from the database. In query processing, it takes various steps for fetching the data from the database. The steps involved are: Parsing and translation. Optimization.
What is query processing with example?
Query Processing is a translation of high-level queries into low-level expression. It is a step wise process that can be used at the physical level of the file system, query optimization and actual execution of the query to get the result. It requires the basic concepts of relational algebra and file structure.
What are the objectives of query processing?
➢The main objectives of query processing in a distributed environment is to form a high level query on a distributed database, which is seen as a single database by the users, into an efficient execution strategy expressed in a low level language in local databases.
What are the layers of query processing?
Layers of Query Processing
- Query Decomposition. The first layer decomposes the calculus query into an algebraic query on global relations.
- Data Localization. The input to the second layer is an algebraic query on global relations.
- Global Query Optimization.
- Distributed Query Execution.
What is the role of query processor?
The query processor is the subcomponent of the data server that processes SQL requests. The SQL requests can access a single database or file system or reference multiple types of databases or file systems. Accesses and joins information from multiple data sources and performs updates to a single data source.
Which is first step in query processing?
Which of the following are steps in query processing? Explanation: Parsing and translation, optimization, evaluation are all the basic steps to process a query.
