delphi fdmemtable 变更转sql脚本

 fdmemtable 变更记录  转 sql

fdmemtable.cachedupdates = true

然后才能获取

{
  转载的  做了细微修改，网址忘了
 引用 System.JSON;

  函数名称：DBToJSON（TFDMemTable 数据转成SQL脚本更新）

  参数：
  DB：TFDMemTable数据集
  sTable：更新表名
  sKey:关键字段，写法：ID,Name 以逗号区分
  sNoField:不需要修改或增加的字段： 写法：ID,Sex  以逗号区分
}
function DBToJSON(const DB:TFDMemTable;sTable:string;sKey:String;sNoField:String):String;
Var
  ItemKey,ItemNoField:TStringlist;
  JA:TJSONArray;
  sField,sValue,sSQL,sTmp,sName:string;
  i,j:Integer;
begin

  JA:=TJSONArray.Create;
  ItemKey:=TStringlist.Create;
  ItemNoField:=TStringlist.Create;

  ItemKey.Delimiter:=',';
  ItemKey.DelimitedText:=sKey;

  ItemNoField.Delimiter:=',';
  ItemNoField.DelimitedText:=sNoField;

  sField:='';
  sValue:='';
  sSQL:='';
  with DB.Delta.DataView.Rows do begin
    for I := 0 to Count-1 do  begin
       sField:='';
      sValue:='';
      sSQL:='';
      //判断数据的操作状态 :插入
      if ItemsI[i].RowState=TFDDatSRowState.rsInserted then begin

        //循环对应的数据字段
        for j := 0 to DB.Fields.Count-1 do begin
        if DB.Fields[J].DataType = ftAutoInc then   Continue;
          //获取字段名称

          sName:=DB.Fields[J].FieldName;

          //排除不需要插入的字段信息
          if ItemNoField.IndexOf(sName)>-1 then
            Continue;




          //判断字段的数据类型
          case DB.Fields[J].DataType of
            ftString,ftWideString,ftMemo: sTmp:=VarToStr(ItemsI[i].GetValues(sName)).QuotedString;
            ftSmallint, ftInteger,ftFloat, ftCurrency, ftBCD,ftAutoInc: sTmp:=VarToStr(ItemsI[i].GetValues(sName));
            ftDateTime: begin
              sTmp:=VarToStr(ItemsI[i].GetValues(sName));
              //日期如何没有填写默认为Null
              if sTmp='' then
                sTmp:='Null'
              else
                sTmp:=FormatDateTime('yyyy-mm-dd hh:ss:mm',StrToDateTime(sTmp)).QuotedString;
            end;
            ftBoolean: begin
              if ItemsI[i].GetValues(sName)=True then
                sTmp:='1'
              else
                sTmp:='0';
            end;
            else
             sTmp:=VarToStr(ItemsI[i].GetValues(sName)).QuotedString;
          end;

          //累积字段和插入值

          sField:=sField+sName+',';
          sValue:=sValue+sTmp+',';

        end;
        //拼接成SQL并插入到数组中
        JA.Add('Insert Into '+sTable+' ('+Copy(sField,1,Length(sField)-1)+')'+#13#10
          +' Values('+Copy(sValue,1,Length(sValue)-1)+')'+#13#10 ) ;

      end
      //判断数据的操作状态 :修改
      else if ItemsI[i].RowState in [TFDDatSRowState.rsModified,
        TFDDatSRowState.rsEditing] then begin

        for j := 0 to DB.Fields.Count-1 do begin
          sName:=DB.Fields[J].FieldName;

          //排除不需要插入的字段信息
          if ItemNoField.IndexOf(sName)>-1 then
            Continue;

          //判断字段的数据类型
          case DB.Fields[J].DataType of
            ftString,ftWideString,ftMemo: sTmp:=VarToStr(ItemsI[i].GetValues(sName)).QuotedString;
            ftSmallint, ftInteger,ftFloat, ftCurrency, ftBCD,ftAutoInc: sTmp:=VarToStr(ItemsI[i].GetValues(sName));
            ftDateTime: begin
              sTmp:=VarToStr(ItemsI[i].GetValues(sName));
              if sTmp='' then
                sTmp:='Null'
              else
                sTmp:=FormatDateTime('yyyy-mm-dd hh:ss:mm',StrToDateTime(sTmp)).QuotedString;
            end;
            ftBoolean: begin
              if ItemsI[i].GetValues(sName)=True then
                sTmp:='1'
              else
                sTmp:='0';
            end;
            else
             sTmp:=VarToStr(ItemsI[i].GetValues(sName)).QuotedString;
          end;

          //累积更新字段值
          if DB.Fields[J].DataType <> ftAutoInc then
          sField:=sField+sName+'='+sTmp+',';

          //修改数据关键字段，条件值
          if ItemKey.IndexOf(sName)>-1 then
            sSQL:=sSQL+' And '+ sName+' = '+VarToStr(ItemsI[i].GetData(sName,rvOriginal));

        end;
        //拼接成SQL并插入到数组中
        JA.Add('Update '+sTable+' Set '+Copy(sField,1,Length(sField)-1)+' Where '+Copy(sSQL,5,Length(sSQL)) );
      end
      else if ItemsI[i].RowState in [TFDDatSRowState.rsDeleted] then begin
        sSQL:='';
        //删除数据关键字段，条件值
        for J := 0 to ItemKey.Count-1 do begin
          sValue:=ItemsI[i].GetValues(ItemKey.Strings[j]);
          if sValue.Trim<>'' then
            sSQL:=sSQL+' And '+ ItemKey.Strings[j]+' = '+QuotedStr(sValue.Trim);
        end;

        //拼接成SQL并插入到数组中
        if sSQL<>'' then
          JA.Add('Delete '+sTable+' Where '+Copy(sSQL,5,Length(sSQL)) );
      end;
    end;
  end;
  Result:=JA.ToString;
  FreeAndNil(JA);
  FreeAndNil(ItemKey);
  FreeAndNil(ItemNoField);

end;

//用法
{
lsql := DBToJSON(MemReport,'tem_fodcd','id','') ;
  ShowMessage(lsql);
    if lsql = '[]' then   Exit;
  ja := TJSONObject.ParseJSONValue(TEncoding.UTF8.GetBytes(lsql),0) as TJSONArray;
  lsql := '';
  for I := 0 to ja.Count - 1 do
    begin
      lsql := lsql + ja.Items[i].Value + ';';
    end;
  ja.Free;
  lsql := StringReplace(lsql,'''','''',[rfReplaceAll]);
}