CCF_100/relational
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Enable down_to_unions_subtractions_intersections

Browse Source
This commit is contained in:
Salvo 'LtWorf' Tomaselli 2020-06-09 11:50:58 +02:00
parent 403b7b9962
commit 418e293c1d
No known key found for this signature in database
GPG Key ID: B3A7CF0C801886CF
1 changed files with 6 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
relational/optimizations.py
View File

@ -175,7 +175,7 @@ def futile_union_intersection_subtraction(n: parser.Node) -> Tuple[parser.Node,
return n, 0
def down_to_unions_subtractions_intersections(n: parser.Node) -> int:
def down_to_unions_subtractions_intersections(n: parser.Node) -> Tuple[parser.Node, int]:
'''This funcion locates things like σ i==2 (c ᑌ d), where the union
can be a subtraction and an intersection and replaces them with
σ i==2 (c) ᑌ σ i==2(d).
@ -183,27 +183,11 @@ def down_to_unions_subtractions_intersections(n: parser.Node) -> int:
changes = 0
_o = (UNION, DIFFERENCE, INTERSECTION)
if n.name == SELECTION and n.child.name in _o:
l = parser.Unary(SELECTION, n.prop, n.child.left)
r = parser.Unary(SELECTION, n.prop, n.child.right)
left = parser.Node()
left.prop = n.prop
left.name = n.name
left.child = n.child.left
left.kind = parser.UNARY
right = parser.Node()
right.prop = n.prop
right.name = n.name
right.child = n.child.right
right.kind = parser.UNARY
n.name = n.child.name
n.left = left
n.right = right
n.child = None
n.prop = None
n.kind = parser.BINARY
changes += 1
return changes + recoursive_scan(down_to_unions_subtractions_intersections, n)
return parser.Binary(n.child.name, l, r), 1
return n, 0
def duplicated_projection(n: parser.Node) -> Tuple[parser.Node, int]:
@ -677,7 +661,7 @@ def useless_projection(n, rels) -> int:
general_optimizations = [
duplicated_select,
#down_to_unions_subtractions_intersections,
down_to_unions_subtractions_intersections,
duplicated_projection,
#selection_inside_projection,
#subsequent_renames,