ekuiper-new/internal/binder/function/funcs_window.go

// Copyright 2023 EMQ Technologies Co., Ltd.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package function

import (
	"github.com/lf-edge/ekuiper/pkg/api"
	"github.com/lf-edge/ekuiper/pkg/ast"
)

func registerWindowFunc() {
	builtins["row_number"] = builtinFunc{
		fType: ast.FuncTypeWindow,
		// we implement window functions in windowFuncOperator instead of exec.
		exec: func(ctx api.FunctionContext, args []interface{}) (interface{}, bool) {
			return nil, true
		},
		val: ValidateNoArg,
	}
}