* href="https://github.com/google/guava/wiki/GraphsExplained#accessor-behavior">the external
 * documentation</a> for details.
 *
 * <p>Examples of use:
 *
 * {@snippet :
 * // Building a mutable graph
 * MutableGraph<String> graph = GraphBuilder.undirected().allowsSelfLoops(true).build();
 * graph.putEdge("bread", "bread");
 * graph.putEdge("chocolate", "peanut butter");
 * graph.putEdge("peanut butter", "jelly");
 *

 * href="https://github.com/google/guava/wiki/GraphsExplained#accessor-behavior">the external
 * documentation</a> for details.
 *
 * <p>Examples of use:
 *
 * {@snippet :
 * // Building a mutable value graph
 * MutableValueGraph<String, Double> graph =
 *     ValueGraphBuilder.undirected().allowsSelfLoops(true).build();
 * graph.putEdgeValue("San Francisco", "San Francisco", 0.0);

	if DB.Dialector.Name() != "mysql" {
		t.Skip()
	}

	type MyTable struct {
		Def string `gorm:"size:512;index:idx_def,unique"`
		Abc string `gorm:"size:65000000"`
	}

	DB.Migrator().DropTable("my_tables")

	sql := "CREATE TABLE `my_tables` (`def` varchar(512),`abc` longtext,UNIQUE INDEX `idx_def` (`def`))"
	if err := DB.Exec(sql).Error; err != nil {

      AvlNode<E> newRoot = new AvlNode<>(element, occurrences);
      successor(header, newRoot, header);
      rootReference.checkAndSet(root, newRoot);
      return 0;
    }
    int[] result = new int[1]; // used as a mutable int reference to hold result
    AvlNode<E> newRoot = root.add(comparator(), element, occurrences, result);
    rootReference.checkAndSet(root, newRoot);
    return result[0];
  }

  @CanIgnoreReturnValue

 *
 * <p>This class maintains a map of nodes to {@link GraphConnections}.
 *
 * <p>Collection-returning accessors return unmodifiable views: the view returned will reflect
 * changes to the graph (if the graph is mutable) but may not be modified by the user.
 *
 * <p>The time complexity of all collection-returning accessors is O(1), since views are returned.
 *
 * @author James Sexton
 * @author Joshua O'Madadhain
 * @author Omar Darwish

 * directed graphs, and an arbitrary endpoint of the edge on undirected graphs.
 *
 * <p>Collection-returning accessors return unmodifiable views: the view returned will reflect
 * changes to the graph (if the graph is mutable) but may not be modified by the user.
 *
 * <p>The time complexity of all collection-returning accessors is O(1), since views are returned.
 *
 * @author James Sexton
 * @author Joshua O'Madadhain
 * @author Omar Darwish

 * href="https://github.com/google/guava/wiki/GraphsExplained#accessor-behavior">the external
 * documentation</a> for details.
 *
 * <p>Examples of use:
 *
 * {@snippet :
 * // Building a mutable network
 * MutableNetwork<String, Integer> network =
 *     NetworkBuilder.directed().allowsParallelEdges(true).build();
 * flightNetwork.addEdge("LAX", "ATL", 3025);
 * flightNetwork.addEdge("LAX", "ATL", 1598);

  }

  private static <T extends @Nullable Object> List<T> shuffledCopy(List<T> in, Random random) {
    List<T> mutable = new ArrayList<>(in);
    List<T> out = new ArrayList<>();
    while (!mutable.isEmpty()) {
      out.add(mutable.remove(random.nextInt(mutable.size())));
    }
    return out;
  }

  }

  private static <T extends @Nullable Object> List<T> shuffledCopy(List<T> in, Random random) {
    List<T> mutable = new ArrayList<>(in);
    List<T> out = new ArrayList<>();
    while (!mutable.isEmpty()) {
      out.add(mutable.remove(random.nextInt(mutable.size())));
    }
    return out;
  }

  public boolean equals(@Nullable Object object) {
    return Maps.equalsImpl(this, object);
  }

  @Override
  public int hashCode() {
    // not caching hash code since it could change if map values are mutable
    // in a way that modifies their hash codes
    return entrySet().hashCode();
  }

  @Override
  public String toString() {
    return Maps.toStringImpl(this);
  }