Add support for SHOW WARNINGS and SELECTs without a FROM (#2227)

Like SELECT 1, 'a';

Author: Jille

internal/compiler/output_columns.go

@@ -102,6 +102,24 @@ func outputColumns(qc *QueryCatalog, node ast.Node) ([]*Column, error) {
 		}
 		switch n := res.Val.(type) {
 
+		case *ast.A_Const:
+			name := ""
+			if res.Name != nil {
+				name = *res.Name
+			}
+			switch n.Val.(type) {
+			case *ast.String:
+				cols = append(cols, &Column{Name: name, DataType: "text", NotNull: true})
+			case *ast.Integer:
+				cols = append(cols, &Column{Name: name, DataType: "int", NotNull: true})
+			case *ast.Float:
+				cols = append(cols, &Column{Name: name, DataType: "float", NotNull: true})
+			case *ast.Boolean:
+				cols = append(cols, &Column{Name: name, DataType: "bool", NotNull: true})
+			default:
+				cols = append(cols, &Column{Name: name, DataType: "any", NotNull: false})
+			}
+
 		case *ast.A_Expr:
 			name := ""
 			if res.Name != nil {

internal/endtoend/testdata/diff_no_output/go/query.sql.go

@@ -46,9 +46,9 @@
 +SELECT 1
 +`
 +
-+func (q *Queries) SelectOne(ctx context.Context) (interface{}, error) {
++func (q *Queries) SelectOne(ctx context.Context) (int32, error) {
 +	row := q.db.QueryRowContext(ctx, selectOne)
-+	var column_1 interface{}
++	var column_1 int32
 +	err := row.Scan(&column_1)
 +	return column_1, err
 +}

internal/endtoend/testdata/diff_output/stderr.txt

@@ -0,0 +1,2 @@
+-- name: SelectStatic :one
+SELECT 'a', 'b' AS b, 1 AS num, true AS truefield, 1.0 AS floater

internal/endtoend/testdata/selectstatic/mysql/go/db.go

@@ -0,0 +1,13 @@
+{
+  "version": "1",
+  "packages": [
+    {
+      "path": "go",
+      "sql_package": "database/sql",
+      "engine": "mysql",
+      "name": "querytest",
+      "schema": "query.sql",
+      "queries": "query.sql"
+    }
+  ]
+}