Enable QUALIFY without GROUP BY / WHERE / HAVING (#38)

* Enable `QUALIFY` without `GROUP BY` / `WHERE` / `HAVING`

* handle error

driver.go

@@ -85,9 +85,13 @@ func newZetaSQLiteConn(db *sql.DB, catalog *internal.Catalog) (*ZetaSQLiteConn,
 	if err != nil {
 		return nil, fmt.Errorf("failed to get sqlite3 connection: %w", err)
 	}
+	analyzer, err := internal.NewAnalyzer(catalog)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create analyzer: %w", err)
+	}
 	return &ZetaSQLiteConn{
 		conn:     conn,
-		analyzer: internal.NewAnalyzer(catalog),
+		analyzer: analyzer,
 	}, nil
 }
 

internal/analyzer.go

@@ -20,15 +20,19 @@ type Analyzer struct {
 	opt             *zetasql.AnalyzerOptions
 }
 
-func NewAnalyzer(catalog *Catalog) *Analyzer {
+func NewAnalyzer(catalog *Catalog) (*Analyzer, error) {
+	opt, err := newAnalyzerOptions()
+	if err != nil {
+		return nil, err
+	}
 	return &Analyzer{
 		catalog:  catalog,
-		opt:      newAnalyzerOptions(),
+		opt:      opt,
 		namePath: &NamePath{},
-	}
+	}, nil
 }
 
-func newAnalyzerOptions() *zetasql.AnalyzerOptions {
+func newAnalyzerOptions() (*zetasql.AnalyzerOptions, error) {
 	langOpt := zetasql.NewLanguageOptions()
 	langOpt.SetNameResolutionMode(zetasql.NameResolutionDefault)
 	langOpt.SetProductMode(types.ProductInternal)
@@ -90,11 +94,17 @@ func newAnalyzerOptions() *zetasql.AnalyzerOptions {
 		ast.CreateViewStmt,
 		ast.DropFunctionStmt,
 	})
+	// Enable QUALIFY without WHERE
+	//https://github.com/google/zetasql/issues/124
+	err := langOpt.EnableReservableKeyword("QUALIFY", true)
+	if err != nil {
+		return nil, err
+	}
 	opt := zetasql.NewAnalyzerOptions()
 	opt.SetAllowUndeclaredParameters(true)
 	opt.SetLanguage(langOpt)
 	opt.SetParseLocationRecordType(zetasql.ParseLocationRecordFullNodeScope)
-	return opt
+	return opt, nil
 }
 
 func (a *Analyzer) SetAutoIndexMode(enabled bool) {

query_test.go

@@ -1807,7 +1807,6 @@ FROM UNNEST(['c', NULL, 'b', 'a']) AS x`,
 				{"a", nil, "a", "c"},
 			},
 		},
-
 		{
 			name: "window range",
 			query: `
@@ -3037,6 +3036,15 @@ FROM Produce WHERE Produce.category = 'vegetable' QUALIFY rank <= 3`,
 				{"cabbage", int64(3)},
 			},
 		},
+		// Regression test goccy/go-zetasqlite#123
+		{
+			name: "qualify without group by / where / having",
+			query: `WITH toks AS (SELECT 1 AS x UNION ALL SELECT 2 AS x)
+			SELECT x FROM toks QUALIFY MAX(x) OVER (PARTITION BY x) > 1`,
+			expectedRows: [][]interface{}{
+				{int64(2)},
+			},
+		},
 		// Regression test goccy/go-zetasqlite#150
 		{
 			name: "qualify group",