Removed redundant check
Assuming that the query is correct, the removed condition must always be true.
This commit is contained in:
parent
3b3888e9be
commit
d384a902cf
@ -558,7 +558,6 @@ def projection_and_union(n, rels):
|
|||||||
if n.name in {UNION, INTERSECTION, DIFFERENCE} and \
|
if n.name in {UNION, INTERSECTION, DIFFERENCE} and \
|
||||||
n.left.name == PROJECTION and \
|
n.left.name == PROJECTION and \
|
||||||
n.right.name == PROJECTION and \
|
n.right.name == PROJECTION and \
|
||||||
set(n.left.result_format(rels)) == set(n.right.result_format(rels)) and \
|
|
||||||
set(n.left.child.result_format(rels)) == set(n.right.child.result_format(rels)):
|
set(n.left.child.result_format(rels)) == set(n.right.child.result_format(rels)):
|
||||||
newchild = parser.Node()
|
newchild = parser.Node()
|
||||||
|
|
||||||
@ -577,7 +576,6 @@ def projection_and_union(n, rels):
|
|||||||
return changes + recoursive_scan(projection_and_union, n, rels)
|
return changes + recoursive_scan(projection_and_union, n, rels)
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
def selection_and_product(n, rels):
|
def selection_and_product(n, rels):
|
||||||
'''This function locates things like σ k (R*Q) and converts them into
|
'''This function locates things like σ k (R*Q) and converts them into
|
||||||
σ l (σ j (R) * σ i (Q)). Where j contains only attributes belonging to R,
|
σ l (σ j (R) * σ i (Q)). Where j contains only attributes belonging to R,
|
||||||
|
Loading…
x
Reference in New Issue
Block a user