BUILDING BASIC STRECH SQL COMPILER

BUILDING BASIC STRECH SQL COMPILER

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  1 Headline Goes Here SpeakerName or Subhead Goes Here DO NOT USE PUBLICLY PRIOR TO 10/23/12 Structured Query Language (SQL) Compiler Mentor : Mr. Ashish Pandey Sir
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  Objective: 2 Introduction to SQL-compiler. LanguageProcessing lex/flex and implementation? Demonstration yacc/ bison and implementation SQL compiler : Working Model Tools and technologies ? Functionality
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  Introduction 3 SQL Structured Query Language Standardized language forrequesting 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
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  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
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  lex/flex Lex is ascanner 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.
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  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 …
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  lex input FIRST PART %% Patternaction …. %% THIRD PART
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  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.
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  using lex % lexexI .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)
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  lex pattern examples abcMatch 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 -.
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  11 yacc/ bison What isyacc/bison ? Hows does it works ?
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  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
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  yacc and lexused 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.
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  lex / yacc 14 mylang.yy.tab.c lex.yy.c y.tab.h mylang.l yacc gcc lex Source code mylang Compiled code /interpreted output
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  Yaac input 15 FIRST PART %% Productionaction %% THIRD PART
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  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).
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  yacc example production 17 Sourcecode a = b + c * d Lexical analyzer Syntax analyzer Id1 = id2 + id3 * id4 yacc lex patterns grammar = id1 + id2 * id3 id4
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  TOOLS USED Operating System •LINUX Software • Flex/ lex , Bison/ Yaac • gcc compiler • gedit
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  TECHNOLOGIES USED C++ Object orientedTechniques Flex Analyzer implementation Bison / YACC programming technique
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  FUNCTIONALITY Compiles the sqlqueries Parses the given commands Detects the errors Compiler frontened analyses the source code Manages the symbol table
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  21  Ashwin Shahi Ankit Verma  Ajeet Dubey sql_compiler@gmail.com