BUILDING BASIC STRECH SQL COMPILER
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The document outlines a structured query language (SQL) compiler that translates high-level SQL statements into lower-level code using tools like Lex/Flex and Yacc/Bison. It covers the components of the SQL compiler, including lexical analysis, parsing, and semantic processing, along with examples and operational details. The implementation utilizes C++ and is developed on a Linux platform, detailing the functionalities such as error detection and symbol table management.
![lex pattern examples
abc Match the string “abc”.
[a-z, A-Z] Match any lower or uppercase letter.
dog.*cat Match any string starting with dog. And ending with cat.
(ab)+ Match one or more occurrences of “ab”.
[^a-z] Matches any string of one or more characters that do not
include lowercase a-z.
[+ -]?[0-9]+ Match any string of one or more digits with an optional prefix of
+ or -.](https://image.slidesharecdn.com/compiler-150525095125-lva1-app6891/85/BUILDING-BASIC-STRECH-SQL-COMPILER-10-320.jpg)
BUILDING BASIC STRECH SQL COMPILER
- 1. 1 Headline Goes Here Speaker Name or Subhead Goes Here DO NOT USE PUBLICLY PRIOR TO 10/23/12 Structured Query Language (SQL) Compiler Mentor : Mr. Ashish Pandey Sir
- 2. Objective: 2 Introduction to SQL-compiler. Language Processing lex/flex and implementation? Demonstration yacc/ bison and implementation SQL compiler : Working Model Tools and technologies ? Functionality
- 3. Introduction 3 SQL Structured Query Language Standardized language for requesting information from a database. COMPILER Program that translates source code into object code high-level language statements into a lower-level representation. SQL + COMPILER SQL-COMPILER
- 4. 4 Scanner (lexical analysis) Machine-specific code improvement (optional) Parser (syntax analysis) Symantic analysis and code generation Machine-independent code improvement(optional) Target code generation Source file (character stream) Token stream Parse Tree Abstract syntax tree Modified intermediate form Target language Modified target language Language Processing
- 5. lex/flex Lex is a scanner generator. Input is a set of regular expression and associated (written in c). Output is a table driven scanner(lex.yy.c). Flex: an source implementation of the original UNIX lex utility.
- 6. Lexical analysis void swap (int *v1, int *v2) { int tmp; tmp = *v1; *v1 = *v2; *v2 = tmp; } Scanner: produces a stream of tokens from the input source } ; tmp ( voidswap Parser …
- 7. lex input FIRST PART %% Pattern action …. %% THIRD PART
- 8. lex input example (I) Filename: ex I .I %% “hello world” printf(“Goodbyen”) ; . ; %% Prints “Goodbye” anytime the string “hello world” is encountered. Does nothing for anyother character.
- 9. using lex % lex exI .I % cc lex.yy.c -II % ./a.out hello world Goodbye % Process the lex file to generate a scanner(gets saved as lex.yy.c) Run the scanner taking input from standard input. Compile the scanner and grab main() from the lex library (-ll option)
- 10. lex pattern examples abc Match the string “abc”. [a-z, A-Z] Match any lower or uppercase letter. dog.*cat Match any string starting with dog. And ending with cat. (ab)+ Match one or more occurrences of “ab”. [^a-z] Matches any string of one or more characters that do not include lowercase a-z. [+ -]?[0-9]+ Match any string of one or more digits with an optional prefix of + or -.
- 11. 11 yacc/ bison What is yacc/bison ? Hows does it works ?
- 12. 12 Scanner (lexical analysis) Machine-specific code improvement (optional) Parser (syntax analysis) Symantic analysis and code generation Machine-independent code improvement(optional) Target code generation Source file (character stream) Token stream Parse Tree Abstract syntax tree Modified intermediate form Target language Modified target language Language Processing
- 13. yacc and lex used together 13 Lex: semantic analysis Splits the input file into tokens yacc: yet another compiler compiler Parses and does semantic processing on the stream of tokens produced by lex Bison: GNU parser parser.
- 14. lex / yacc 14 mylang.y y.tab.c lex.yy.c y.tab.h mylang.l yacc gcc lex Source code mylang Compiled code /interpreted output
- 15. Yaac input 15 FIRST PART %% Production action %% THIRD PART
- 16. yacc productions 16 $1 , $2 …… $n can be refer to the values associated with symbols $$ refer to the value of the left. Default action : $$ = $1 Every symbol have a value associated with it (including token and non-terminals).
- 17. yacc example production 17 Source code a = b + c * d Lexical analyzer Syntax analyzer Id1 = id2 + id3 * id4 yacc lex patterns grammar = id1 + id2 * id3 id4
- 18. TOOLS USED Operating System • LINUX Software • Flex/ lex , Bison/ Yaac • gcc compiler • gedit
- 19. TECHNOLOGIES USED C++ Object oriented Techniques Flex Analyzer implementation Bison / YACC programming technique
- 20. FUNCTIONALITY Compiles the sql queries Parses the given commands Detects the errors Compiler frontened analyses the source code Manages the symbol table
- 21. 21 Ashwin Shahi Ankit Verma Ajeet Dubey sql_compiler@gmail.com