Mysql-Lösung zur Optimierung der Paging-Abfrage für große Tabellen

/**
	 * 如果是根据创建时间排序的分页，根据上一条记录的创建时间优化分布查询
	 * 
	 * @see 将会自动添加createTime排序
	 * @param lastEndCreateTime
	 *            上一次查询的最后一条记录的创建时间
	 * @param lastEndCount 上一次查询的时间为lastEndCreateTime的数量
	 * @param lastEndOffset  上一次查询的最后一条记录对应的偏移量     offset+limit
	 **/
	public Page<T> page(QueryBuilder queryBuilder, Date lastEndCreateTime, Integer lastEndCount, Integer lastEndOffset,
			int offset, int limit) {
		FromBuilder fromBuilder = queryBuilder.from(getModelClass());
		Page<T> page = new Page<>();
		int count = dao.count(fromBuilder);
		page.setTotal(count);
		if (count == 0) {
			return page;
		}
		if (offset == 0 || lastEndCreateTime == null || lastEndCount == null || lastEndOffset == null) {
			List<T> list = dao.find(
					SelectBuilder.selectFrom(fromBuilder.offsetLimit(offset, limit).order().desc("createTime").end()));
			page.setData(list);
			return page;
		}
		boolean isForward = offset >= lastEndOffset;
		if (isForward) {
			int calcOffset = offset - lastEndOffset + lastEndCount;
			int calcOffsetFormEnd = count - offset - limit;
			if (calcOffsetFormEnd <= calcOffset) {
				isForward = false;
				if (calcOffsetFormEnd > 0) {
					fromBuilder.order().asc("createTime").end().offsetLimit(calcOffsetFormEnd, limit);
				} else {
					fromBuilder.order().asc("createTime").end().offsetLimit(0, calcOffsetFormEnd + limit);
				}
			} else {
				fromBuilder.where().andLe("createTime", lastEndCreateTime).end().order().desc("createTime").end()
						.offsetLimit(calcOffset, limit);
			}
		} else {
			fromBuilder.where().andGe("createTime", lastEndCreateTime).end().order().asc("createTime").end()
					.offsetLimit(lastEndOffset - offset - limit - 1 + lastEndCount, limit);
		}
		List<T> list = dao.find(SelectBuilder.selectFrom(fromBuilder));
		if (!isForward) {
			list.sort(new Comparator<T>() {
				@Override
				public int compare(T o1, T o2) {
					return o1.getCreateTime().before(o2.getCreateTime()) ? 1 : -1;
				}
			});
		}
		page.setData(list);
		return page;
	}<p> </p>
<p>Front-End-JS-Parameter, basierend auf der Bootstrap-Tabelle</p>
<pre class="brush:php;toolbar:false">    this.lastEndCreateTime = null;
    this.currentEndCreateTime = null;
    
    this.isRefresh = false;        
      this.currentEndOffset = 0;
        this.lastEndOffset = 0;
        this.lastEndCount = 0;
        this.currentEndCount = 0;
        $("#" + this.tableId).bootstrapTable({
            url: url,
            method: 'get',
            contentType: "application/x-www-form-urlencoded",//请求数据内容格式 默认是 application/json 自己根据格式自行服务端处理
            dataType:"json",
            dataField:"data",
            pagination: true,
            sidePagination: "server", // 服务端请求
            pageList: [10, 25, 50, 100, 200],
            search: true,
            showRefresh: true,
            toolbar: "#" + tableId + "Toolbar",
            iconSize: "outline",
            icons: {
                refresh: "icon fa-refresh",
            },
            queryParams: function(params){
            	if(params.offset == 0){
            		this.currentEndOffset = params.offset + params.limit;
            	}else{
            		if(params.offset + params.limit==this.currentEndOffset){ 
            			//刷新
            			this.isRefresh = true;
            			params.lastEndCreateTime = this.lastEndCreateTime;
                		params.lastEndOffset = this.lastEndOffset;
                		params.lastEndCount = this.lastEndCount;
            		}else{ 
            			console.log(this.currentEndCount);
            			//跳页
            			this.isRefresh = false;
            			params.lastEndCreateTime = this.currentEndCreateTime;
                		params.lastEndOffset = this.currentEndOffset;
                		params.lastEndCount = this.currentEndCount;
                		this.lastEndOffset = this.currentEndOffset;
                		this.currentEndOffset = params.offset + params.limit;
                		console.log(params.lastEndOffset+","+params.lastEndCreateTime);
                		
            		}
            	}
            	return params;
            },
            onSearch: function (text) {
                this.keyword = text;
            },
            onPostBody : onPostBody,
            onLoadSuccess: function (resp) {
            	
            	if(resp.code!=0){
            		alertUtils.error(resp.msg);
            	}
               
                var data = resp.data;
                var dateLength = data.length;
                if(dateLength==0){
                	return;
                }
                if(!this.isRefresh){
                	 this.lastEndCreateTime =  this.currentEndCreateTime;
                     this.currentEndCreateTime = data[data.length-1].createTime;
                     this.lastEndCount = this.currentEndCount;
                     this.currentEndCount = 0;
                     for (var i = 0; i < resp.data.length; i++) {
						var item = resp.data[i];
						if(item.createTime === this.currentEndCreateTime){
							this.currentEndCount++;
						}
					}
                }
                
            }
        });