SCC is a tool, which allows you to migrate data from the relational to the graph database. As the relational database language was chosen Microsoft SQL for the Microsoft SQL Server. The MS SQL is translated to the Cypher Query Language for the neo4j graph database.

It is important to note, that SCC translates one file with queries per cycle. It means, that our converter doesn't analyze all queries to know more about your database structure. Every query from the input file is translated apart from each other. Keep this in mind when using our product. h

1. Opportunities. What queries can be converted?
2. Operating principle
3. Installation
   1. Linux
   2. Windows
   3. MacOS
4. Launch
   1. First run
   2. Usage
      1. Configuration via file
      2. Configuration via console flags
5. How to conduct testing?
   1. GoogleTest
   2. Write your own unit-tests
6. Documentation
7. Authors
8. Mentors

At first, we planned, that the SCC will convert standard DDL and DML queries. It can be the simplest query, for example:

CREATE DATABASE Zoo;

or

CREATE TABLE Aviaries (
    aviary_id integer,
    square float,
    PRIMARY KEY (aviary_id)
);
CREATE TABLE Zones (
    zone_id integer,
    PRIMARY KEY (zone_id)
);

or

ALTER TABLE Aviaries
    ADD
        zone_id integer,
        CONSTRAINT fk_aviaries_zones
        FOREIGN KEY (aviary_id)
        REFERENCES Zones (zone_id);

as DDL queries. Also, we plan to implement translation for the DML queries.

Every SQL query from the input file goes through the following path:

1. Tokenization (Parsing on the tokens with own type, like as word, operator, etc.);

This step is the common parsing. The query will be introduce as tokens array at the end of tokenization.

3. Syntax Analyses (Analyzer introduces tokens array into AST);

SCC analyses tokens array via recursive descent and builds AST of the query.

4. AST handler (Preparing the AST to translation);

Notice: for now, this module is not implemented.

It is an intermediate step between the Analysis and Translation. The handler leads the AST to the correct introduction for the translation.

5. Query Assembler (AST analysing and translation into CQL).

Translation. The Assembler analyses the AST and searches for constructions for translation.

We plan to make portable versions of the SCC to the all popular OS along with accompanying installation instructions.

1. Go to the Release page and download a .deb package;
2. Go to package directory and use the following command for installation:

$ sudo dpkg -i package_name.deb

This command will install the SCC on your linux. 3. Use the SCC with

$ scc -v

You will see the following message:

$ scc -v
<===| SCC (The SQL to CypherQL Converter) |===>
Version:     0.9.0
Developers:  Artyom Fartygin, Roman Korostinskiy

Save your time with the SCC!

1. Go to the Release page and download a .exe package;
2. Go to package directory and run installer. You will see NSIS window with with the installation steps;
3. Use the SCC with the Windows' command line:

$ scc -v

You will see the following message:

$ scc -v
<===| SCC (The SQL to CypherQL Converter) |===>
Version:     0.9.0
Developers:  Artyom Fartygin, Roman Korostinskiy

Save your time with the SCC!

For now, the SCC can't be installed in the MacOS via installer, but you can use local application. See Launch.

Our project can be compiled via CMake. Use the following steps:

1. Build the SCC:

sql2cypher/ $ cmake -S . -B build [options]

where options:

• -DPACKAGE=0, if you want to use the SCC locally;
• -DPACKAGE=1, if you want to create package;

If you will create a package, you can manually set an OS:

• -DWIN32=1 for Windows package (.exe). With this option you must have MinGW and add new option: -G "MinGW Makefiles";
• -DUNIX=1 for Linux package (.deb).

2. Run the converter locally:

sql2cypher/ $ cd build/
sql2cypher/build/ $ ./SCC

You will see the following INFO messages:

[INFO]  <Time> main.cpp: main(): 4: Starting system...
[INFO]  <Time> main.cpp: main(): 6: System started

3. If you are creating a package for Linux or Windows you should go to build directory and run the following command:

sql2cypher/build/ $ make package

You will see new file with .deb or .exe extension.

The SCC can be configured by the config.ini file in the root directory and via console flags. Let's look at these opportunities.

Notice: will be implemented in the future patches.

Usage:
   scc --sql=file1 --cypher=file2 [options]...
Options:
-h, --help          Prints Usage and information about acceptable flags.
-v, --version       Prints current version.
-m, --mode=[mode]   Starts the SCC in special mode (by default: interactive)
-i, --interactive   Starts the SCC in interactive mode.
--dump=[path]       Creates Tree Dump image of the AST in the [path].
-l, --loglvl=lvl    Sets logging level to "lvl".
                    Acceptable levels: SILENT, FATAL, ERROR, INFO, TRACE, DEBUG.
--logdir=[path]     Path to the log directory, where will be created log file
--sql=[path]        Path to the file with SQL queries, which will be converted (SQL).
--cypher=[path]     Path to the file, where will be converted queries (CQL).
--dump=[path]       Path to the file, where will be created image of AST of SQL queries
                    (by default, the image is not created)

We use GoogleTest framework for the unit-testing. Go to the build folder, which was created previously, and run the following command:

sql2cypher/build/ $ ctest

you will see something like this:

Test project /path/to/sql2cypher/build
      Start  1: SetGetConfigTests.DefaultConfigTest
 1/17 Test  #1: SetGetConfigTests.DefaultConfigTest ..........   Passed    0.02 sec
      Start  2: SetGetConfigTests.ValidModeTest
 2/17 Test  #2: SetGetConfigTests.ValidModeTest ..............   Passed    0.02 sec
...
      Start 17: AddLogTests.AddInvalidLogTest
17/17 Test #17: AddLogTests.AddInvalidLogTest ................   Passed    0.04 sec

100% tests passed, 0 tests failed out of 16

Total Test time (real) =   0.47 sec

You can learn GoogleTest via this User Guide.

If you want to test some feature, you should to write your own tests and put your test file into the test/ directory. Don't forget to change CMakeLists.txt!

We plan to write some Wiki pages on the GitHub and use Doxygen for generating documentation. We think, it will be useful for you.

For now you can generate docs with Doxygen. Go to the root of the app directory and use the following command:

sql2cypher/ $ doxygen doc/doxygen-config.dox

Artyom Fartygin (temikfart) — Undergraduate student at MIPT PAMI

Roman Korostinskiy (RomanKorostinskiy) — Undergraduate student at MIPT PRCT

Nikolay Efanov (nefanov) — Associate professor at MIPT