sql: add not visible index to optimizer

This commit adds the logic of the invisible index feature to the optimizer.
After this commit has been merged, the invisible index feature should be fully
functional with `CREATE INDEX` and `CREATE TABLE`.

Assists: cockroachdb#72576

See also: cockroachdb#85239

Release note (sql change): creating a not visible index using
`CREATE TABLE …(INDEX … NOT VISIBLE)` or
`CREATE INDEX … NOT VISIBLE` is now supported.

pkg/sql/create_index.go

@@ -736,12 +736,6 @@ func (n *createIndexNode) startExec(params runParams) error {
 		)
 	}
 
-	if n.n.NotVisible {
-		return unimplemented.Newf(
-			"Not Visible Index",
-			"creating a not visible index is not supported yet")
-	}
-
 	// Warn against creating a non-partitioned index on a partitioned table,
 	// which is undesirable in most cases.
 	// Avoid the warning if we have PARTITION ALL BY as all indexes will implicitly

pkg/sql/create_table.go

@@ -1777,11 +1777,6 @@ func NewTableDesc(
 					return nil, pgerror.Newf(pgcode.DuplicateRelation, "duplicate index name: %q", d.Name)
 				}
 			}
-			if d.NotVisible {
-				return nil, unimplemented.Newf(
-					"Not Visible Index",
-					"creating a not visible index is not supported yet")
-			}
 			if err := validateColumnsAreAccessible(&desc, d.Columns); err != nil {
 				return nil, err
 			}
@@ -1886,11 +1881,6 @@ func NewTableDesc(
 				// We will add the unique constraint below.
 				break
 			}
-			if d.NotVisible {
-				return nil, unimplemented.Newf(
-					"Not Visible Index",
-					"creating a not visible index is not supported yet")
-			}
 			// If the index is named, ensure that the name is unique. Unnamed
 			// indexes will be given a unique auto-generated name later on when
 			// AllocateIDs is called.