Method GetIndexSpecification

IO/MySQL/vtkMySQLDatabase.cxx:501–560

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//------------------------------------------------------------------------------
vtkStdString vtkMySQLDatabase::GetIndexSpecification(
  vtkSQLDatabaseSchema* schema, int tblHandle, int idxHandle, bool& skipped)
{
  skipped = false;
  vtkStdString queryStr = ", ";
  bool mustUseName = true;

  int idxType = schema->GetIndexTypeFromHandle(tblHandle, idxHandle);
  switch (idxType)
  {
    case vtkSQLDatabaseSchema::PRIMARY_KEY:
      queryStr += "PRIMARY KEY ";
      mustUseName = false;
      break;
    case vtkSQLDatabaseSchema::UNIQUE:
      queryStr += "UNIQUE ";
      break;
    case vtkSQLDatabaseSchema::INDEX:
      queryStr += "INDEX ";
      break;
    default:
      return vtkStdString();
  }

  // No index_name for PRIMARY KEYs
  if (mustUseName)
  {
    queryStr += schema->GetIndexNameFromHandle(tblHandle, idxHandle);
  }
  queryStr += " (";

  // Loop over all column names of the index
  int numCnm = schema->GetNumberOfColumnNamesInIndex(tblHandle, idxHandle);
  if (numCnm < 0)
  {
    vtkGenericWarningMacro(
      "Unable to get index specification: index has incorrect number of columns " << numCnm);
    return {};
  }

  bool firstCnm = true;
  for (int cnmHandle = 0; cnmHandle < numCnm; ++cnmHandle)
  {
    if (firstCnm)
    {
      firstCnm = false;
    }
    else
    {
      queryStr += ",";
    }
    // With MySQL, the column name must be enclosed between backquotes
    queryStr += "`";
    queryStr += schema->GetIndexColumnNameFromHandle(tblHandle, idxHandle, cnmHandle);
    queryStr += "` ";
  }
  queryStr += ")";