db: respect changed filters in SetOptions

Rebuild the iterator stack if filters (block or table) are modified.

Fix cockroachdb#1621.

data_test.go

@@ -152,14 +152,22 @@ func runIterCmd(d *datadriven.TestData, iter *Iterator, closeIter bool) string {
 			iter.SetBounds(lower, upper)
 			valid = iter.Valid()
 		case "set-options":
-			const usageString = "set-options [lower=<lower>] [upper=<upper>] [key-types=point|range|both] [mask-suffix=<suffix>]\n"
+			const usageString = "set-options [lower=<lower>] [upper=<upper>] [key-types=point|range|both] [mask-suffix=<suffix>] [only-durable=<bool>] [table-filter=reuse|none] [point-filters=reuse|none]\n"
 			var opts IterOptions
 			for _, part := range parts[1:] {
 				arg := strings.SplitN(part, "=", 2)
 				if len(arg) != 2 {
 					return usageString
 				}
 				switch arg[0] {
+				case "point-filters":
+					switch arg[1] {
+					case "reuse":
+						opts.PointKeyFilters = iter.opts.PointKeyFilters
+					case "none":
+					default:
+						return fmt.Sprintf("set-options: unknown arg point-filter=%q:\n%s", arg[1], usageString)
+					}
 				case "lower":
 					opts.LowerBound = []byte(arg[1])
 				case "upper":
@@ -177,6 +185,20 @@ func runIterCmd(d *datadriven.TestData, iter *Iterator, closeIter bool) string {
 					}
 				case "mask-suffix":
 					opts.RangeKeyMasking.Suffix = []byte(arg[1])
+				case "table-filter":
+					switch arg[1] {
+					case "reuse":
+						opts.TableFilter = iter.opts.TableFilter
+					case "none":
+					default:
+						return fmt.Sprintf("set-options: unknown arg table-filter=%q:\n%s", arg[1], usageString)
+					}
+				case "only-durable":
+					var err error
+					opts.OnlyReadGuaranteedDurable, err = strconv.ParseBool(arg[1])
+					if err != nil {
+						return err.Error()
+					}
 				default:
 					return fmt.Sprintf("set-options: unknown arg %q:\n%s", arg[0], usageString)
 				}

iterator.go

@@ -1739,11 +1739,33 @@ func (i *Iterator) SetOptions(o *IterOptions) {
 	}
 	i.iterValidityState = IterExhausted
 
+	var closePoint, closeRange bool
 	// If OnlyReadGuaranteedDurable changed, the iterator stacks are incorrect,
 	// improperly including or excluding memtables. Invalidate them so that
 	// finishInitializingIter will reconstruct them.
-	if i.opts.OnlyReadGuaranteedDurable != o.OnlyReadGuaranteedDurable {
+	closePoint = closePoint || i.opts.OnlyReadGuaranteedDurable != o.OnlyReadGuaranteedDurable
+
+	// If either the original options or the new options specify a table filter,
+	// we need to reconstruct the iterator stacks. If they both supply a table
+	// filter, we can't be certain that it's the same filter since we have no
+	// mechanism to compare the filter closures.
+	closePoint = closePoint || i.opts.TableFilter != nil || o.TableFilter != nil
+	closeRange = closeRange || i.opts.TableFilter != nil || o.TableFilter != nil
+
+	// If either options specify block property filters for an iterator stack,
+	// reconstruct it.
+	// TODO(jackson): Expose a InternalIterator.SetOptions function and
+	// propagate changed filters to the existing iterator stack. There will
+	// likely be complications with determinism.
+	closePoint = closePoint || len(i.opts.PointKeyFilters) > 0 || len(o.PointKeyFilters) > 0
+	closeRange = closeRange || len(i.opts.RangeKeyFilters) > 0 || len(o.RangeKeyFilters) > 0
+
+	if closePoint && i.pointIter != nil {
+		i.err = firstError(i.err, i.pointIter.Close())
 		i.pointIter = nil
+	}
+	if closeRange && i.rangeKey != nil {
+		i.err = firstError(i.err, i.rangeKey.iter.Close())
 		i.rangeKey = nil
 	}
 

testdata/iterator_block_interval_filter

@@ -253,6 +253,37 @@ d0704:d
 d0704:d
 .
 
+# Repeat the above test, but calling set-options before iteration to set the
+# same filter. The results should be identical.
+iter id_lower_upper=(3,4,5) id_lower_upper=(5,7,9)
+set-options point-filters=reuse
+first
+next
+prev
+prev
+----
+.
+d0704:d
+.
+d0704:d
+.
+
+# Repeat the above test, but calling set-options before iteration to remove the
+# filter.
+iter id_lower_upper=(3,4,5) id_lower_upper=(5,7,9)
+set-options point-filters=none
+first
+next
+prev
+prev
+----
+.
+a1001:a
+b0902:b
+a1001:a
+.
+
+
 # Iterate with filter id=3 and id=5, where the two admitted sets are
 # non-empty, but the intersection is empty.
 iter id_lower_upper=(3,4,5) id_lower_upper=(5,8,9)

testdata/iterator_table_filter

@@ -48,3 +48,19 @@ iter filter=1
 first
 ----
 .
+
+# Set-options that reuses the filter should still see the filter apply.
+# Set-options that removes the filter should not.
+
+iter filter=4
+first
+set-options table-filter=reuse
+first
+set-options table-filter=none
+first
+----
+a:3
+.
+a:3
+.
+a:4