pg: leading zeros in pginterp

kwilteam · Sep 5, 2024 · 05a1873 · 05a1873
1 parent 3864569
commit 05a1873
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Showing 2 changed files with 71 additions and 3 deletions.
diff --git a/internal/sql/pg/histo.go b/internal/sql/pg/histo.go
@@ -323,7 +323,7 @@ func interpNum[T Num](f float64, a, b T) T {
 }
 
 func interpBig(f float64, a, b *big.Int) *big.Int {
-	if b.Cmp(a) <= 0 {
+	if b.Cmp(a) == -1 {
 		panic("b must not be less than a")
 	}
 
@@ -372,7 +372,11 @@ func interpBts(f float64, a, b []byte) []byte {
 }
 
 func interpUUID(f float64, a, b types.UUID) types.UUID {
-	return types.UUID(interpBts(f, a[:], b[:]))
+	bts := interpBts(f, a[:], b[:])
+	if len(bts) != 16 {
+		bts = append(make([]byte, 16-len(bts)), bts...)
+	}
+	return types.UUID(bts)
 }
 
 func interpUUIDPtr(f float64, a, b *types.UUID) *types.UUID {

diff --git a/internal/sql/pg/histo_test.go b/internal/sql/pg/histo_test.go
@@ -10,9 +10,11 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/kwilteam/kwil-db/common/sql"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+
+	"github.com/kwilteam/kwil-db/common/sql"
+	"github.com/kwilteam/kwil-db/core/types"
 )
 
 func Test_histo_explicit_int(t *testing.T) {
@@ -699,3 +701,65 @@ func Test_restoreHisto(t *testing.T) {
 	require.NotNil(t, ht.comp)
 	assert.Equal(t, ht.comp(1, 2), -1)
 }
+
+func TestInterpUUID(t *testing.T) {
+	tests := []struct {
+		name     string
+		f        float64
+		a        types.UUID
+		b        types.UUID
+		expected types.UUID
+	}{
+		{
+			name:     "result with leading zeros",
+			f:        0.5,
+			a:        types.UUID{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+			b:        types.UUID{0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
+			expected: types.UUID{0x00, 0x7F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
+		},
+		{
+			name:     "Zero interpolation",
+			f:        0,
+			a:        types.UUID{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+			b:        types.UUID{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
+			expected: types.UUID{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+		},
+		{
+			name:     "Full interpolation",
+			f:        1,
+			a:        types.UUID{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+			b:        types.UUID{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
+			expected: types.UUID{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
+		},
+		{
+			name:     "Mid interpolation",
+			f:        0.5,
+			a:        types.UUID{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+			b:        types.UUID{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
+			expected: types.UUID{0x7F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
+		},
+		{
+			name:     "Quarter interpolation",
+			f:        0.25,
+			a:        types.UUID{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+			b:        types.UUID{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
+			expected: types.UUID{0x3F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
+		},
+		{
+			name:     "Interpolation with same UUIDs",
+			f:        0.5,
+			a:        types.UUID{0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF, 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF},
+			b:        types.UUID{0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF, 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF},
+			expected: types.UUID{0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF, 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := interpUUID(tt.f, tt.a, tt.b)
+			if result != tt.expected {
+				t.Errorf("interpUUID(%v, %v, %v) = %v, want %v", tt.f, tt.a, tt.b, result, tt.expected)
+			}
+		})
+	}
+}