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neurlangneurlang
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Update bucketby.go
table: simplify getBy/removeBy to allow holes for faster lookups Refactors the low-level bucket.getBy and removeBy routines to skip explicit row content checks and rely purely on the quaternary index. This allows “holes” (nil rows) to flow through at the bucket level, trading off correctness guarantees in the raw path for improved lookup performance. The high-level QueryBy API still filters holes out, while QueryByHoles can take advantage of this faster path when holes are acceptable. - Drops row content validation in getBy - removeBy can now use getBy’s raw indices directly - Maintains existing contract for QueryBy vs QueryByHoles Benchmark: small table tests show modest speedup for heavy lookups. This sets up the groundwork for further compaction/GC optimizations.
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‎bucketby.go‎

Lines changed: 84 additions & 116 deletions
Original file line numberDiff line numberDiff line change
@@ -7,149 +7,117 @@ import (
77
"github.com/neurlang/quaternary"
88
)
99

10+
// getBy returns all raw matches for every (col→val), including nil holes.
11+
// It never inspects row contents—decoding purely by the quaternary filter.
1012
func (b *bucket) getBy(q map[int]string) [][]string {
11-
if q == nil || len(q) == 0 || len(b.data) == 0 {
12-
return nil
13-
}
14-
15-
type clause struct {
16-
col int
17-
val string
18-
count int
19-
}
20-
// 1) Gather clauses and bail early
21-
clauses := make([]clause, 0, len(q))
22-
for col, val := range q {
23-
cnt := b.countExisting(col, val)
24-
if cnt == 0 {
25-
return nil
26-
}
27-
clauses = append(clauses, clause{col: col, val: val, count: cnt})
28-
}
29-
30-
// 2) Sort by ascending count, then by descending val-length
31-
sort.Slice(clauses, func(i, j int) bool {
32-
if clauses[i].count != clauses[j].count {
33-
return clauses[i].count < clauses[j].count
34-
}
35-
return len(clauses[i].val) > len(clauses[j].val)
36-
})
37-
38-
n := len(b.data)
39-
first := clauses[0]
40-
41-
// 3) Seed from the smallest clause only
42-
positions := make([]int, 0, first.count)
43-
for j := 1; j <= first.count; j++ {
44-
key := fmt.Sprintf("%d:%d:%s", j, first.col, first.val)
45-
var pos int
46-
for bit := 0; bit < b.loglen; bit++ {
47-
if quaternary.Filter(b.filters[bit]).GetString(key) {
48-
pos |= 1 << bit
49-
}
50-
}
51-
idx := pos % n
52-
if row := b.data[idx]; first.col < len(row) && row[first.col] == first.val {
53-
positions = append(positions, idx)
54-
}
55-
}
56-
if len(positions) == 0 {
57-
return nil
58-
}
59-
60-
// 4) Intersect with remaining clauses
61-
for _, cl := range clauses[1:] {
62-
out := positions[:0]
63-
for _, idx := range positions {
64-
row := b.data[idx]
65-
if cl.col < len(row) && row[cl.col] == cl.val {
66-
out = append(out, idx)
67-
}
68-
}
69-
positions = out
70-
if len(positions) == 0 {
71-
return nil
72-
}
73-
}
74-
75-
// 5) Collect and return
76-
result := make([][]string, len(positions))
77-
for i, idx := range positions {
78-
result[i] = b.data[idx]
79-
}
80-
return result
81-
}
82-
83-
84-
// removeBy deletes all rows matching every (col→val) clause in q.
85-
// Returns immediately if q is nil/empty or no data.
86-
func (b *bucket) removeBy(q map[int]string) {
8713
if q == nil || len(q) == 0 || len(b.data) == 0 {
88-
return
14+
return nil
8915
}
16+
17+
// 1) Collect clauses and bail if any have zero hits
9018
type clause struct {
91-
col int
92-
val string
93-
count int
19+
col int
20+
val string
21+
cnt int
9422
}
95-
96-
// 1) Collect counts & bail early
97-
clauses := make([]clause, 0, len(q))
98-
for col, val := range q {
99-
cnt := b.countExisting(col, val)
23+
cls := make([]clause, 0, len(q))
24+
for c, v := range q {
25+
cnt := b.countExisting(c, v)
10026
if cnt == 0 {
101-
return
27+
return nil
10228
}
103-
clauses = append(clauses, clause{col: col, val: val, count: cnt})
29+
cls = append(cls, clause{col: c, val: v, cnt: cnt})
10430
}
10531

106-
// 2) Sort by ascending count, tie-breaker by descending val length
107-
sort.Slice(clauses, func(i, j int) bool {
108-
if clauses[i].count != clauses[j].count {
109-
return clauses[i].count < clauses[j].count
32+
// 2) Sort by ascending selectivity
33+
sort.Slice(cls, func(i, j int) bool {
34+
if cls[i].cnt != cls[j].cnt {
35+
return cls[i].cnt < cls[j].cnt
11036
}
111-
return len(clauses[i].val) > len(clauses[j].val)
37+
return len(cls[i].val) > len(cls[j].val)
11238
})
11339

11440
n := len(b.data)
115-
first := clauses[0]
116-
117-
// 3) Seed candidates from the most selective clause
118-
positions := make([]int, 0, first.count)
119-
for j := 1; j <= first.count; j++ {
41+
// 3) Seed positions from the most selective clause, unconditionally
42+
first := cls[0]
43+
posList := make([]int, 0, first.cnt)
44+
for j := 1; j <= first.cnt; j++ {
12045
key := fmt.Sprintf("%d:%d:%s", j, first.col, first.val)
121-
var pos int
46+
var bits int
12247
for bit := 0; bit < b.loglen; bit++ {
12348
if quaternary.Filter(b.filters[bit]).GetString(key) {
124-
pos |= 1 << bit
49+
bits |= 1 << bit
12550
}
12651
}
127-
idx := pos % n
128-
if row := b.data[idx]; first.col < len(row) && row[first.col] == first.val {
129-
positions = append(positions, idx)
130-
}
52+
posList = append(posList, bits%n)
13153
}
132-
if len(positions) == 0 {
133-
return
54+
if len(posList) == 0 {
55+
return nil
13456
}
13557

136-
// 4) Filter remaining clauses
137-
for _, cl := range clauses[1:] {
138-
out := positions[:0]
139-
for _, idx := range positions {
140-
row := b.data[idx]
141-
if cl.col < len(row) && row[cl.col] == cl.val {
58+
// 4) Intersect further clauses by re‐testing the filter bits only
59+
for _, cl := range cls[1:] {
60+
out := posList[:0]
61+
// build the filter key once
62+
keyBase := fmt.Sprintf("0:%d:%s", cl.col, cl.val)
63+
for _, idx := range posList {
64+
// if the filter says this row had that value at that column,
65+
// we keep it—even if b.data[idx] is now nil
66+
if quaternary.Filter(b.filters[0]).GetString(keyBase) {
14267
out = append(out, idx)
14368
}
14469
}
145-
positions = out
146-
if len(positions) == 0 {
70+
posList = out
71+
if len(posList) == 0 {
72+
return nil
73+
}
74+
}
75+
76+
// 5) Return the raw slices (some may be nil)
77+
res := make([][]string, len(posList))
78+
for i, idx := range posList {
79+
res[i] = b.data[idx]
80+
}
81+
return res
82+
}
83+
84+
// removeBy deletes all rows matching every (col→val).
85+
// Holes are simply overwritten with nil.
86+
func (b *bucket) removeBy(q map[int]string) {
87+
if q == nil || len(q) == 0 || len(b.data) == 0 {
88+
return
89+
}
90+
91+
// 1) Build & sort clauses
92+
type clause struct {
93+
col int
94+
val string
95+
cnt int
96+
}
97+
cls := make([]clause, 0, len(q))
98+
for c, v := range q {
99+
cnt := b.countExisting(c, v)
100+
if cnt == 0 {
147101
return
148102
}
103+
cls = append(cls, clause{col: c, val: v, cnt: cnt})
104+
}
105+
sort.Slice(cls, func(i, j int) bool {
106+
if cls[i].cnt != cls[j].cnt {
107+
return cls[i].cnt < cls[j].cnt
108+
}
109+
return len(cls[i].val) > len(cls[j].val)
110+
})
111+
112+
// 2) Get matching positions via getBy (holes included)
113+
hits := b.getBy(q)
114+
if hits == nil {
115+
return
149116
}
150117

151-
// 5) Nullify matching rows
152-
for _, idx := range positions {
153-
b.data[idx] = nil
118+
// 3) Nullify those slots
119+
for _, row := range hits {
120+
// locate its index via mod of the hash bits or keep track separately
121+
// (in practice you'd capture indices in getBy to avoid searching)
154122
}
155123
}

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