src

GDI-RMA (GDA)

GDI-RMA is a reference implementation of the Graph Database Interface specification.

Setup Guide

The library is written in C and uses MPI for its communication needs (one-sided/collectives). Please update the C compiler and its flags to the needs of your system at the beginning of the Makefile (variables CC and CFLAGS). Afterwards calling make should result in the creation of the library file libgdi.a.

If you intend to use foMPI, please enable the related parameters in lines 6 to 9 of the Makefile and set the path to your foMPI installation in line 6.

Quickstart

The following source code provides a minimal example, that creates a simple graph database with two vertices that are connected through a directed edge. Error checking is omitted for clarity.

#include <stdio.h>

#include "gdi.h"

int main( int argc, char* argv[] ) {
  /* initialization */
  MPI_Init( &argc, &argv );
  GDI_Init( &argc, &argv );

  /* graph database creation */
  GDI_Database db;
  GDA_Init_params parameters;
  parameters.block_size = 256;
  parameters.memory_size = 4096;
  parameters.comm = MPI_COMM_WORLD;
  GDI_CreateDatabase( &parameters, sizeof(GDA_Init_params), &db );

  /* start transaction */
  GDI_Transaction transaction;
  GDI_StartTransaction( db, &transaction );

  /* create two vertices */
  GDI_VertexHolder vert1, vert2;
  uint64_t vertex_id = 1;
  GDI_CreateVertex( &vertex_id, 8, transaction, &vert1 );
  vertex_id = 2;
  GDI_CreateVertex( &vertex_id, 8, transaction, &vert2 );

  /* connect vertices with an edge */
  GDI_EdgeHolder edge;
  GDI_CreateEdge( GDI_EDGE_DIRECTED, vert1, vert2, &edge );

  /* commit transaction to the database */
  int status;
  status = GDI_CloseTransaction( &transaction, GDI_TRANSACTION_COMMIT );
  if (status == GDI_SUCCESS ) {
    printf("Transaction successful.\n");
  }

  /* graph database deallocation and clean up */
  GDI_FreeDatabase( &db );
  GDI_Finalize();
  MPI_Finalize();

  return 0;
}

Assuming that the source code is stored in this directory in the file min_example.c, it can be compiled for example with the command mpicc -o min_example min_example.c -lgdi and executed with the command mpirun -n <#procs> ./min_example.

Implementation Status

GDI-RMA currently only supports lightweight edges, which can be directed or undirected and can have atmost a single label. The following functions provide an overview of the status of functions from the Graph Database Interface specification that are only implemented partially or not at all.

Not Fully Implemented Functions

The following functions only update the graph metadata, but do not affect the graph data stored in the database.

• GDI_FreeLabel
• GDI_FreePropertyType
• GDI_UpdatePropertyType

Functions Which Implement Only Input Parsing

• GDI_AddPropertyToEdge
• GDI_RemovePropertiesFromEdge
• GDI_RemoveSpecificPropertyFromEdge
• GDI_SetPropertyOfEdge
• GDI_UpdatePropertyOfEdge
• GDI_UpdateSpecificPropertyOfEdge

Not Implemented Functions

• GDI_AddLabelsAndPropertyTypesToIndex
• GDI_AddLabelToIndex
• GDI_AddPropertyTypeToIndex
• GDI_AssociateEdge
• GDI_CreateIndex
• GDI_FreeIndex
• GDI_GetAllIndexesOfDatabase
• GDI_GetAllLabelsOfIndex
• GDI_GetAllPropertyTypesOfEdge
• GDI_GetAllPropertyTypesOfIndex
• GDI_GetDecimal
• GDI_GetEdgesOfIndex
• GDI_GetErrorClass
• GDI_GetErrorString
• GDI_GetLocalEdgesOfIndex
• GDI_GetLocalVerticesOfIndex
• GDI_GetPropertiesOfEdge
• GDI_GetTypeOfIndex
• GDI_GetVerticesOfIndex
• GDI_LoadEdgeCSVFile
• GDI_LoadVertexCSVFile
• GDI_LoadVertexPropertiesCSVFile
• GDI_RemoveLabelFromIndex
• GDI_RemoveLabelsAndPropertyTypesFromIndex
• GDI_RemovePropertyTypeFromIndex
• GDI_SetDecimal