- To implement Query processor with initial goals of implementing Query Compiler that contains Query Parser: Syntactic Parsing and Semantic Parsing.
- In Between User Applications and Storage Manager of RDBMS.
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Query Parser output is Query Expression Tree. |
- Query Compiler:
- Lexical Analysis
- Syntactic Analysis
- Semantic Analysis
- Query Optimization
- DDL Interpreter doesn't require Query Optimisation
- The job of the parser is to take text written in a language such as SQL and convert into a Parse Tree.
- Tree whose nodes correspond to either:
- Atoms: lexical elements such as keywords, names of attributes or relations, constants, parentheses, operators such as + or <, and other schema elements
- Syntactic Categories: names for families of query subparts that all play a similar role in the query.
