README.md in bmg-0.18.0 vs README.md in bmg-0.18.1
- old
+ new
@@ -211,9 +211,10 @@
r.constants(x: 12, ...) # add constant attributes (sometimes useful in unions)
r.extend(x: ->(t){ ... }, ...) # add computed attributes
r.exclude(predicate) # shortcut for restrict(!predicate)
r.group([:a, :b, ...], :x) # relation-valued attribute from attributes
r.image(right, :x, [:a, :b, ...]) # relation-valued attribute from another relation
+r.images({:x => r1, :y => r2}, [:a, ...]) # shortcut over image(r1, :x, ...).image(r2, :y, ...)
r.join(right, [:a, :b, ...]) # natural join on a join key
r.join(right, :a => :x, :b => :y, ...) # natural join after right reversed renaming
r.left_join(right, [:a, :b, ...], {...}) # left join with optional default right tuple
r.left_join(right, {:a => :x, ...}, {...}) # left join after right reversed renaming
r.matching(right, [:a, :b, ...]) # semi join, aka where exists