Developer Documentation ======================= ## Basic Requirements **Requirements for development:** * gcc 4.8+ (or clang 3.4+) * [bison](https://www.gnu.org/software/bison/) (v3.0.2+) * [flex](http://flex.sourceforge.net/) (v2.5.5+) First step to extending this parser is cloning the repository `git clone git@github.com:hyrise/sql-parser.git` and making sure everything works by running the following steps: ```bash make parser # builds the bison parser and flex lexer make library # builds the libsqlparser.so make test # runs the tests with the library ``` Rerun these steps whenever you change part of the parse. To execute the entire pipeline automatically you can run: ```bash make cleanall # cleans the parser build and library build make test # build parser, library and runs the tests ``` ## Developing New Functionality This section contains information about how to extend this parser with new functionalities. ### Implementing a new Statement Create a new file and class in `src/sql/` or extend any of the existing Statements. Every statement needs to have the base class SQLStatement and needs to call its super constructor with its type. If your defining a new statement type, you need to define a new StatementType in `SQLStatement.h`. It is important that you create an appropriate constructor for your statement that zero-initializes all its pointer variables and that your create an appropriate destructor. Finally you will need to include your new file in `src/sql/statements.h`. ### Extending the Grammar Related files: ``` src/parser/bison_parser.y src/parser/flex_lexer.l src/parser/keywordlist_generator.py src/parser/sql_keywords.txt ``` To extend the grammar the file you will mostly have to deal with is the bison grammar definition in `src/parser/bison_parser.y`. If your extending an existing statement, skip to the non-terminal definition for that statement. I.e. for an InsertStatement the non-terminal insert_statement. If your defining a new statement, you will need to define your type in the \%union directive `hsql::ExampleStatement example_stmt`. Next you need to associate this type with a non-terminal `\%type example_statement`. Then you have to define the non-terminal `example_statement`. Look the other non-terminals for statements to figure out how. ## Implementing Tests All test related files are in `test/`. Take a look to see how tests are implemented.