return "CONSTRAINT ? UNIQUE (?)", []interface{}{clause.Column{Name: uni.Name}, clause.Column{Name: uni.Field.DBName}}
}

// ParseUniqueConstraints parse schema unique constraints
func (schema *Schema) ParseUniqueConstraints() map[string]UniqueConstraint {
	uniques := make(map[string]UniqueConstraint)
	for _, field := range schema.Fields {
		if field.Unique {

          // Came to an empty slot. Put the element here.
          elements[uniques++] = element;
          table[index] = element;
          hashCode += hash;
          break;
        } else if (value.equals(element)) {
          break;
        }
      }
    }
    Arrays.fill(elements, uniques, n, null);
    if (uniques == 1) {
      // There is only one element or elements are all duplicates

      int uniques = 1;
      for (int i = 1; i < sortedElements.length; i++) {
        if (comparator.compare(sortedElements[uniques - 1], sortedElements[i]) < 0) {
          sortedElements[uniques] = sortedElements[i];
          uniques++;
        }
      }
      Arrays.fill(sortedElements, uniques, length, null);
      if (maybeExpand && uniques * 4 > length * 3) {

    Arrays.sort(contents, 0, n, comparator);
    int uniques = 1;
    for (int i = 1; i < n; i++) {
      E cur = contents[i];
      E prev = contents[uniques - 1];
      if (comparator.compare(cur, prev) != 0) {
        contents[uniques++] = cur;
      }
    }
    Arrays.fill(contents, uniques, n, null);
    if (uniques < contents.length / 2) {

    checkElementsNotNull(contents, n);
    Arrays.sort(contents, 0, n, comparator);
    int uniques = 1;
    for (int i = 1; i < n; i++) {
      E cur = contents[i];
      E prev = contents[uniques - 1];
      if (comparator.compare(cur, prev) != 0) {
        contents[uniques++] = cur;
      }
    }
    Arrays.fill(contents, uniques, n, null);
    return new RegularImmutableSortedSet<>(

Vous devez vous assurer qu'il est unique pour chaque opération.

```Python hl_lines="6"

### New unique package

The new [unique](/pkg/unique) package provides facilities for
canonicalizing values (like "interning" or "hash-consing").

Any value of comparable type may be canonicalized with the new
`Make[T]` function, which produces a reference to a canonical copy of
the value in the form of a `Handle[T]`.
Two `Handle[T]` are equal if and only if the values used to produce the
handles are equal, allowing programs to deduplicate values and reduce

}

// UserInfo holds the information about the user needed to implement the
// user.Info interface.
message UserInfo {
  // The name that uniquely identifies this user among all active users.
  // +optional
  optional string username = 1;

  // A unique value that identifies this user across time. If this user is
  // deleted and another user by the same name is added, they will have
  // different UIDs.

)

func bytediff(a, b []byte) string {
	const (
		uniqueA  = "-  "
		uniqueB  = "+  "
		identity = "   "
	)
	var ss []string
	sa := strings.Split(strings.TrimSpace(hex.Dump(a)), "\n")
	sb := strings.Split(strings.TrimSpace(hex.Dump(b)), "\n")
	for len(sa) > 0 && len(sb) > 0 {
		if sa[0] == sb[0] {
			ss = append(ss, identity+sa[0])
		} else {
			ss = append(ss, uniqueA+sa[0])
			ss = append(ss, uniqueB+sb[0])
		}

}

// UserInfo holds the information about the user needed to implement the
// user.Info interface.
message UserInfo {
  // The name that uniquely identifies this user among all active users.
  // +optional
  optional string username = 1;

  // A unique value that identifies this user across time. If this user is
  // deleted and another user by the same name is added, they will have
  // different UIDs.