From da391c3db74b8c1043a0e8a4f81f17f3bd7ce6b2 Mon Sep 17 00:00:00 2001
From: Barak Michener <me@barakmich.com>
Date: Tue, 14 Jul 2015 21:43:09 -0400
Subject: [PATCH] optional index strategies

---
 graph/sql/iterator.go  |  5 ++---
 graph/sql/quadstore.go | 29 +++++++++++++++++++++++++----
 2 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/graph/sql/iterator.go b/graph/sql/iterator.go
index af8a8a7..a0750ef 100644
--- a/graph/sql/iterator.go
+++ b/graph/sql/iterator.go
@@ -95,12 +95,11 @@ func NewIterator(qs *QuadStore, d quad.Direction, val graph.Value) *Iterator {
 }
 
 func NewAllIterator(qs *QuadStore, table string) *Iterator {
-	var size int64
 	it := &Iterator{
 		uid:   iterator.NextUID(),
 		qs:    qs,
 		dir:   quad.Any,
-		size:  size,
+		size:  qs.Size(),
 		table: table,
 		isAll: true,
 	}
@@ -255,7 +254,7 @@ func (it *Iterator) Describe() graph.Description {
 
 func (it *Iterator) Stats() graph.IteratorStats {
 	size, _ := it.Size()
-	if it.table == "nodes" {
+	if it.table == "nodes" || it.isAll {
 		return graph.IteratorStats{
 			ContainsCost: 1,
 			NextCost:     9999,
diff --git a/graph/sql/quadstore.go b/graph/sql/quadstore.go
index e6b7162..c52e942 100644
--- a/graph/sql/quadstore.go
+++ b/graph/sql/quadstore.go
@@ -61,10 +61,31 @@ func createSQLTables(addr string, options graph.Options) error {
 		glog.Errorf("Cannot create quad table: %v", quadTable)
 		return err
 	}
-	index, err := tx.Exec(`
-	CREATE INDEX pos_index ON quads (predicate, object, subject) WITH (FILLFACTOR = 50);
-	CREATE INDEX osp_index ON quads (object, subject, predicate) WITH (FILLFACTOR = 50);
-	`)
+	idxStrat, _, err := options.StringKey("db_index_strategy")
+	factor, factorOk, err := options.IntKey("db_fill_factor")
+	if !factorOk {
+		factor = 50
+	}
+	var index sql.Result
+	if idxStrat == "brin" {
+		index, err = tx.Exec(`
+		CREATE INDEX spo_index ON quads USING brin(subject) WITH (pages_per_range = 32);
+		CREATE INDEX pos_index ON quads USING brin(predicate) WITH (pages_per_range = 32);
+		CREATE INDEX osp_index ON quads USING brin(object) WITH (pages_per_range = 32);
+		`)
+	} else if idxStrat == "prefix" {
+		index, err = tx.Exec(fmt.Sprintf(`
+	CREATE INDEX spo_index ON quads (substr(subject, 0, 8)) WITH (FILLFACTOR = %d);
+	CREATE INDEX pos_index ON quads (substr(predicate, 0, 8)) WITH (FILLFACTOR = %d);
+	CREATE INDEX osp_index ON quads (substr(object, 0, 8)) WITH (FILLFACTOR = %d);
+	`, factor, factor, factor))
+	} else {
+		index, err = tx.Exec(fmt.Sprintf(`
+	CREATE INDEX spo_index ON quads (subject, predicate, object) WITH (FILLFACTOR = %d);
+	CREATE INDEX pos_index ON quads (predicate, object, subject) WITH (FILLFACTOR = %d);
+	CREATE INDEX osp_index ON quads (object, subject, predicate) WITH (FILLFACTOR = %d);
+	`, factor, factor, factor))
+	}
 	if err != nil {
 		glog.Errorf("Cannot create indices: %v", index)
 		return err