Boolean aggregates.

Author: ncruces

ext/stats/TODO.md

@@ -48,10 +48,8 @@ https://sqlite.org/windowfunctions.html#builtins
 
 ## Boolean aggregates
 
-- [ ] `ALL(boolean)`
-- [ ] `ANY(boolean)`
-- [ ] `EVERY(boolean)`
-- [ ] `SOME(boolean)`
+- [X] `EVERY(boolean)`
+- [X] `SOME(boolean)`
 
 ## Additional aggregates
 

ext/stats/boolean.go

@@ -0,0 +1,46 @@
+package stats
+
+import "github.com/ncruces/go-sqlite3"
+
+const (
+	every = iota
+	some
+)
+
+func newBoolean(kind int) func() sqlite3.AggregateFunction {
+	return func() sqlite3.AggregateFunction { return &boolean{kind: kind} }
+}
+
+type boolean struct {
+	count int
+	total int
+	kind  int
+}
+
+func (b *boolean) Value(ctx sqlite3.Context) {
+	if b.kind == every {
+		ctx.ResultBool(b.count == b.total)
+	} else {
+		ctx.ResultBool(b.count > 0)
+	}
+}
+
+func (b *boolean) Step(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	if arg[0].Type() == sqlite3.NULL {
+		return
+	}
+	if arg[0].Bool() {
+		b.count++
+	}
+	b.total++
+}
+
+func (b *boolean) Inverse(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	if arg[0].Type() == sqlite3.NULL {
+		return
+	}
+	if arg[0].Bool() {
+		b.count--
+	}
+	b.total--
+}

ext/stats/boolean_test.go

@@ -0,0 +1,74 @@
+package stats_test
+
+import (
+	"testing"
+
+	"github.com/ncruces/go-sqlite3"
+	_ "github.com/ncruces/go-sqlite3/embed"
+	"github.com/ncruces/go-sqlite3/ext/stats"
+	_ "github.com/ncruces/go-sqlite3/internal/testcfg"
+)
+
+func TestRegister_boolean(t *testing.T) {
+	t.Parallel()
+
+	db, err := sqlite3.Open(":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	stats.Register(db)
+
+	err = db.Exec(`CREATE TABLE data (x)`)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = db.Exec(`INSERT INTO data (x) VALUES (4), (7.0), (13), (NULL), (16), (3.14)`)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	stmt, _, err := db.Prepare(`
+		SELECT
+			every(x > 0),
+			every(x > 10),
+			some(x > 10),
+			some(x > 20)
+		FROM data`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if stmt.Step() {
+		if got := stmt.ColumnBool(0); got != true {
+			t.Errorf("got %v, want true", got)
+		}
+		if got := stmt.ColumnBool(1); got != false {
+			t.Errorf("got %v, want false", got)
+		}
+		if got := stmt.ColumnBool(2); got != true {
+			t.Errorf("got %v, want true", got)
+		}
+		if got := stmt.ColumnBool(3); got != false {
+			t.Errorf("got %v, want false", got)
+		}
+	}
+	stmt.Close()
+
+	stmt, _, err = db.Prepare(`SELECT every(x > 10) OVER (ROWS 1 PRECEDING) FROM data`)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	want := [...]bool{false, false, false, true, true, false}
+	for i := 0; stmt.Step(); i++ {
+		if got := stmt.ColumnBool(0); got != want[i] {
+			t.Errorf("got %v, want %v", got, want[i])
+		}
+		if got := stmt.ColumnType(0); got != sqlite3.INTEGER {
+			t.Errorf("got %v, want INTEGER", got)
+		}
+	}
+	stmt.Close()
+}

ext/stats/stats.go

@@ -21,6 +21,8 @@
 //   - quantile_disc: discrete quantile
 //   - quantile_cont: continuous quantile
 //   - median: median value
+//   - every: boolean and
+//   - some: boolean or
 //
 // These join the [Built-in Aggregate Functions]:
 //   - count: count rows/values
@@ -29,9 +31,16 @@
 //   - min: minimum value
 //   - max: maximum value
 //
+// And the [Built-in Window Functions]:
+//   - rank: rank of the current row with gaps
+//   - dense_rank: rank of the current row without gaps
+//   - percent_rank: relative rank of the row
+//   - cume_dist: cumulative distribution
+//
 // See: [ANSI SQL Aggregate Functions], [DuckDB Aggregate Functions]
 //
 // [Built-in Aggregate Functions]: https://sqlite.org/lang_aggfunc.html
+// [Built-in Window Functions]: https://sqlite.org/windowfunctions.html#builtins
 // [ANSI SQL Aggregate Functions]: https://www.oreilly.com/library/view/sql-in-a/9780596155322/ch04s02.html
 // [DuckDB Aggregate Functions]: https://duckdb.org/docs/sql/aggregates.html
 package stats
@@ -61,6 +70,8 @@ func Register(db *sqlite3.Conn) {
 	db.CreateWindowFunction("median", 1, flags, newQuantile(median))
 	db.CreateWindowFunction("quantile_cont", 2, flags, newQuantile(quant_cont))
 	db.CreateWindowFunction("quantile_disc", 2, flags, newQuantile(quant_disc))
+	db.CreateWindowFunction("every", 1, flags, newBoolean(every))
+	db.CreateWindowFunction("some", 1, flags, newBoolean(some))
 }
 
 const (

ext/stats/stats_test.go

@@ -40,8 +40,6 @@ func TestRegister_variance(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	defer stmt.Close()
-
 	if stmt.Step() {
 		if got := stmt.ColumnFloat(0); got != 40 {
 			t.Errorf("got %v, want 40", got)
@@ -62,24 +60,23 @@ func TestRegister_variance(t *testing.T) {
 			t.Errorf("got %v, want √22.5", got)
 		}
 	}
+	stmt.Close()
 
-	{
-		stmt, _, err := db.Prepare(`SELECT var_samp(x) OVER (ROWS 1 PRECEDING) FROM data`)
-		if err != nil {
-			t.Fatal(err)
-		}
-		defer stmt.Close()
+	stmt, _, err = db.Prepare(`SELECT var_samp(x) OVER (ROWS 1 PRECEDING) FROM data`)
+	if err != nil {
+		t.Fatal(err)
+	}
 
-		want := [...]float64{0, 4.5, 18, 0, 0}
-		for i := 0; stmt.Step(); i++ {
-			if got := stmt.ColumnFloat(0); got != want[i] {
-				t.Errorf("got %v, want %v", got, want[i])
-			}
-			if got := stmt.ColumnType(0); (got == sqlite3.FLOAT) != (want[i] != 0) {
-				t.Errorf("got %v, want %v", got, want[i])
-			}
+	want := [...]float64{0, 4.5, 18, 0, 0}
+	for i := 0; stmt.Step(); i++ {
+		if got := stmt.ColumnFloat(0); got != want[i] {
+			t.Errorf("got %v, want %v", got, want[i])
+		}
+		if got := stmt.ColumnType(0); (got == sqlite3.FLOAT) != (want[i] != 0) {
+			t.Errorf("got %v, want %v", got, want[i])
 		}
 	}
+	stmt.Close()
 }
 
 func TestRegister_covariance(t *testing.T) {
@@ -113,8 +110,6 @@ func TestRegister_covariance(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	defer stmt.Close()
-
 	if stmt.Step() {
 		if got := stmt.ColumnFloat(0); got != 0.9881049293224639 {
 			t.Errorf("got %v, want 0.9881049293224639", got)
@@ -159,24 +154,23 @@ func TestRegister_covariance(t *testing.T) {
 			t.Errorf("got %v, want 5", got)
 		}
 	}
+	stmt.Close()
 
-	{
-		stmt, _, err := db.Prepare(`SELECT covar_samp(y, x) OVER (ROWS 1 PRECEDING) FROM data`)
-		if err != nil {
-			t.Fatal(err)
-		}
-		defer stmt.Close()
+	stmt, _, err = db.Prepare(`SELECT covar_samp(y, x) OVER (ROWS 1 PRECEDING) FROM data`)
+	if err != nil {
+		t.Fatal(err)
+	}
 
-		want := [...]float64{0, 10, 30, 75, 22.5}
-		for i := 0; stmt.Step(); i++ {
-			if got := stmt.ColumnFloat(0); got != want[i] {
-				t.Errorf("got %v, want %v", got, want[i])
-			}
-			if got := stmt.ColumnType(0); (got == sqlite3.FLOAT) != (want[i] != 0) {
-				t.Errorf("got %v, want %v", got, want[i])
-			}
+	want := [...]float64{0, 10, 30, 75, 22.5}
+	for i := 0; stmt.Step(); i++ {
+		if got := stmt.ColumnFloat(0); got != want[i] {
+			t.Errorf("got %v, want %v", got, want[i])
+		}
+		if got := stmt.ColumnType(0); (got == sqlite3.FLOAT) != (want[i] != 0) {
+			t.Errorf("got %v, want %v", got, want[i])
 		}
 	}
+	stmt.Close()
 }
 
 func Benchmark_average(b *testing.B) {

stmt.go

@@ -441,12 +441,12 @@ func (s *Stmt) ColumnOriginName(col int) string {
 // ColumnBool returns the value of the result column as a bool.
 // The leftmost column of the result set has the index 0.
 // SQLite does not have a separate boolean storage class.
-// Instead, boolean values are retrieved as integers,
+// Instead, boolean values are retrieved as numbers,
 // with 0 converted to false and any other value to true.
 //
 // https://sqlite.org/c3ref/column_blob.html
 func (s *Stmt) ColumnBool(col int) bool {
-	return s.ColumnInt64(col) != 0
+	return s.ColumnFloat(col) != 0
 }
 
 // ColumnInt returns the value of the result column as an int.

value.go

@@ -68,12 +68,12 @@ func (v Value) NumericType() Datatype {
 
 // Bool returns the value as a bool.
 // SQLite does not have a separate boolean storage class.
-// Instead, boolean values are retrieved as integers,
+// Instead, boolean values are retrieved as numbers,
 // with 0 converted to false and any other value to true.
 //
 // https://sqlite.org/c3ref/value_blob.html
 func (v Value) Bool() bool {
-	return v.Int64() != 0
+	return v.Float() != 0
 }
 
 // Int returns the value as an int.