code: @Override
      public void deleteByColumn(String schemaName, String tableName, String columnName, Object columnValue) {
          Session session = factory.getConnection();
          String rowKeyName = null;
          CQLTranslator translator = new CQLTranslator();
          try {
              List<ColumnMetadata> primaryKeys = session.getCluster().getMetadata().getKeyspace("\"" + schemaName + "\"")
                  .getTable("\"" + tableName + "\"").getPrimaryKey();
              rowKeyName = primaryKeys.get(0).getName();
          } finally {
              // factory.releaseConnection(session);
          }
  
          List rowKeys =
              getColumnsById(schemaName, tableName, columnName, rowKeyName, columnValue, columnValue.getClass());
          for (Object rowKey : rowKeys) {
              if (rowKey != null) {
                  String deleteQuery = CQLTranslator.DELETE_QUERY;
  
                  deleteQuery = StringUtils.replace(deleteQuery, CQLTranslator.COLUMN_FAMILY,
                      translator.ensureCase(new StringBuilder(), tableName, false).toString());
                  StringBuilder deleteQueryBuilder = new StringBuilder(deleteQuery);
                  deleteQueryBuilder.append(CQLTranslator.ADD_WHERE_CLAUSE);
                  deleteQueryBuilder = translator.ensureCase(deleteQueryBuilder, rowKeyName, false);
                  deleteQueryBuilder.append(CQLTranslator.EQ_CLAUSE);
                  translator.appendValue(deleteQueryBuilder, rowKey.getClass(), rowKey, false, false);
                  this.execute(deleteQueryBuilder.toString(), null);
              }
          }
      }
docs: /*
  (non-Javadoc)
  
  @see com.impetus.kundera.client.Client#deleteByColumn(java.lang.String, java.lang.String, java.lang.String,
  java.lang.Object)