New query optimization

A * B ∪ A * C = A * (B ∪ C)
2015-12-31 14:26:28 +01:00
parent 5c2ff5f844
commit 950a2273c3
4 changed files with 47 additions and 1 deletions
--- a/test/union_join.query
+++ b/test/union_join.query
@@ -0,0 +1 @@
+people⋈σ skill == 'Perl' (skills) ∪ (people⋈σ skill == 'C' (skills))
--- a/test/union_join.result
+++ b/test/union_join.result
@@ -0,0 +1,8 @@
+id,name,chief,age,skill
+4,eve,0,25,C
+5,duncan,4,30,C
+2,john,1,30,C
+7,alia,1,28,C
+4,eve,0,25,Perl
+5,duncan,4,30,Perl
+0,jack,0,22,C
				`@@ -0,0 +1 @@`
				`people⋈σ skill == 'Perl' (skills) ∪ (people⋈σ skill == 'C' (skills))`