github.com/matrixorigin/matrixone@v1.2.0/pkg/vm/engine/tae/tables/handle.go (about)

     1  // Copyright 2021 Matrix Origin
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package tables
    16  
    17  import (
    18  	"github.com/matrixorigin/matrixone/pkg/vm/engine/tae/catalog"
    19  	"github.com/matrixorigin/matrixone/pkg/vm/engine/tae/common"
    20  	"github.com/matrixorigin/matrixone/pkg/vm/engine/tae/iface/data"
    21  )
    22  
    23  type tableHandle struct {
    24  	table    *dataTable
    25  	object   *aobject
    26  	appender data.ObjectAppender
    27  }
    28  
    29  func newHandle(table *dataTable, object *aobject) *tableHandle {
    30  	h := &tableHandle{
    31  		table:  table,
    32  		object: object,
    33  	}
    34  	if object != nil {
    35  		h.appender, _ = object.MakeAppender()
    36  	}
    37  	return h
    38  }
    39  
    40  func (h *tableHandle) SetAppender(id *common.ID) (appender data.ObjectAppender) {
    41  	tableMeta := h.table.meta
    42  	objMeta, _ := tableMeta.GetObjectByID(id.ObjectID())
    43  	h.object = objMeta.GetObjectData().(*aobject)
    44  	h.appender, _ = h.object.MakeAppender()
    45  	h.object.Ref()
    46  	return h.appender
    47  }
    48  
    49  func (h *tableHandle) ThrowAppenderAndErr() (appender data.ObjectAppender, err error) {
    50  	err = data.ErrAppendableObjectNotFound
    51  	h.object = nil
    52  	h.appender = nil
    53  	return
    54  }
    55  
    56  func (h *tableHandle) GetAppender() (appender data.ObjectAppender, err error) {
    57  	var objEntry *catalog.ObjectEntry
    58  	if h.appender == nil {
    59  		objEntry = h.table.meta.LastAppendableObject()
    60  		if objEntry == nil {
    61  			err = data.ErrAppendableObjectNotFound
    62  			return
    63  		}
    64  		h.object = objEntry.GetObjectData().(*aobject)
    65  		h.appender, err = h.object.MakeAppender()
    66  		if err != nil {
    67  			panic(err)
    68  		}
    69  	}
    70  
    71  	dropped := h.object.meta.HasDropCommitted()
    72  	if !h.appender.IsAppendable() || !h.object.IsAppendable() || dropped {
    73  		return h.ThrowAppenderAndErr()
    74  	}
    75  	h.object.Ref()
    76  	// Similar to optimistic locking
    77  	dropped = h.object.meta.HasDropCommitted()
    78  	if !h.appender.IsAppendable() || !h.object.IsAppendable() || dropped {
    79  		h.object.Unref()
    80  		return h.ThrowAppenderAndErr()
    81  	}
    82  	appender = h.appender
    83  	return
    84  }