简介 rowcount和@@rowcount是数据库中两特殊变量。...详解 rowcount rowcount的作用就是用来限定后面的sql在返回指定的行数之后便停止处理,注意rowcount设置会在整个会话中有效,且对修改(update),删除(delete)一样有效。...--类似select top 10 * from table;操作 SQL 要取消set rowcount的限定,只要设置 set rowcount 0 就可以。...@@Rowcount @@Rowcount主要是返回上次sql语句所影响的数据行数,注意删除(delete),修改(update),新增(insert)等语句也会返回值。...但是性能很差,可以使用rowcount来实现,如下: declare @n int set @n=10 set rowcount @n select * from table_A SQL @@rowcount
PDOStatement::rowCount PDOStatement::rowCount — 返回受上一个 SQL 语句影响的行数(PHP 5 = 5.1.0, PECL pdo = 0.1.0)...说明 语法 int PDOStatement::rowCount ( void ) PDOStatement::rowCount()返回上一个由对应的 PDOStatement 对象执行DELETE、...实例 返回删除的行数 PDOStatement::rowCount()返回受 DELETE、INSERT、或 UPDATE 语句影响的行数。 <?...$del- execute(); /* 返回被删除的行数 */ print("Return number of rows that were deleted:\n"); $count = $del- rowCount...计算由一个 SELECT 语句返回的行数 对于大多数数据库,PDOStatement::rowCount()不能返回受一条 SELECT 语句影响的行数。
今天给大家介绍一下TOP、OFFSET-FETCH、SET ROWCOUNT用法笔记,希望对大家能有所帮助!...3、SET ROWCOUNT语句 SET ROWCOUNT n 语句限制结果集的大小,该语句指定在返回指定的n行后停止处理查询。...SET ROWCOUNT与TOP的差别如下: SET ROWCOUNT限制适用于计算ORDER BY后在结果集中生成行。...直到执行下一个SET ROWCOUNT语句前,SET ROWCOUNT设置将一直有效。如果执行SET ROWCOUNT 0将关闭该选项。...说明:TOP和OFFSET-FETCH性能要优于使用SET ROWCOUNT,应当尽量避免使用SET ROWCOUNT。
查询字符串 @currentpage int, –第N页 @pagesize int –每页行数 as set nocount on declare @P1 int, –P1是游标的id @rowcount...int exec sp_cursoropen @P1 output,@sqlstr,@scrollopt=1,@ccopt=1,@rowcount=@rowcount output select...ceiling(1.0*@rowcount/@pagesize) as 总页数–,@rowcount as 总行数,@currentpage as 当前页 set @currentpage=(@currentpage...out select @pagecount as pagecount,@recordcount as recordcount declare @p1 int, @rowcount...=@rowcount output select @p1,@rowcount exec sp_cursorfetch @p1,16,1,20 exec sp_cursorclose @p1
DECLARE游标名CURSOR FOR SELECT不会初始化%ROWCOUNT; SELECT之后,%ROWCOUNT不变,而OPEN游标名之后,%ROWCOUNT不变。...第一个成功的FETCH设置%ROWCOUNT。如果没有行符合查询选择条件,则FETCH设置%ROWCOUNT = 0;否则,设置%ROWCOUNT = 0。...到达数据结尾(SQLCODE = 100)时,%ROWCOUNT包含已检索的行数:/// d ##class(PHA.TEST.SQL).ROWCOUNT()ClassMethod ROWCOUNT().../// d ##class(PHA.TEST.SQL).ROWCOUNT2()ClassMethod ROWCOUNT2(){ TSTART // 开始事务 NEW SQLCODE,%ROWCOUNT...%ROWCOUNT> 0。查询未返回任何数据,在这种情况下,输出主机变量未定义。 %ROWCOUNT = 0。
Hive在估算每个Operator的返回结果RowCount,即中间结果大小,有的是使用元数据对象来进行估算的RowCount;有的使用RelNode自身实现方法估算的;有的是总行数乘以其选择率估算的等多种方法实现...一个Operator返回记录数RowCount,即中间结果的大小直接影响到CostModel成本的大小(返回的RowCount是成本模型Cost Model的记录数、IO、CPU元素之一)。...+= partialRowCount; } return rowCount; } 2) 计算Project的RowCount Project投影,类似指定需要返回的字段列表组成记录,...offset非空的情况下,Sort的RowCount = min(总rowCount,offset + limit),否则用总记录数作为返回值。...()); if (rowCount !
int set @ROWCOUNT=0 insert into TEST_name values(1,1) set @ROWCOUNT=@@ROWCOUNT...=@@ROWCOUNT end if(@ROWCOUNT>0) begin insert into TEST_name...values(3,2) set @ROWCOUNT=@@ROWCOUNT end if(@ROWCOUNT<=0) begin...int set @ROWCOUNT=0 insert into TEST_name values(1,1) set @ROWCOUNT=@@ROWCOUNT...insert into TEST_name values(2,null) set @ROWCOUNT=@@ROWCOUNT end if
); points = new PointF[rowCount * rowCount]; innerCirclePaint = new Paint(Paint.ANTI_ALIAS_FLAG...+ rowCount - 1) * 1.0f; 设置各圆坐标 各圆坐标使用一维数组保存,计算方式为: // 各个圆设置坐标点 for (int i = 0; i < rowCount * rowCount...; i++) { points[i] = new PointF(0, 0); points[i].set((i % rowCount * 3 + 1) * radius, (i / rowCount...void init() { stateSparseArray = new SparseIntArray(rowCount * rowCount); points = new PointF[rowCount...+ rowCount - 1) * 1.0f; // 各个圆设置坐标点 for (int i = 0; i < rowCount * rowCount; i++) { points[i] = new
number(10); begin select count(1) into v_rowcount from user_tables where table_name = upper('z_student...number(5); begin select count(*) into v_rowcount from dual where exists (select 1 from z_student..., phone) VALUES ('001', '张三', '男', '杭州市', 13888888888); end if; commit; end; / declare v_rowcount...'; set @v_rowcount = 0; select count(*) into @v_rowcount from dual where exists (select * from...'; set @v_rowcount = 0; select count(*) into @v_rowcount from dual where exists (select * from
ControlArry">按钮集合 5 /// 父容器 6 /// 9 private void ControlToControlResize(Control[] ControlArry, Control control_parent, int RowCount...; 15 if (ControlArry.Length < RowCount) //定义一列展示的数量大于总控件 16 { 17...} 19 else 20 { 21 yCount = ControlArry.Length % RowCount...ControlArry.Length / RowCount : ControlArry.Length / RowCount + 1; 22 } 23 Padding
String Dim RecordRange As Range Dim FirstAddress As String Dim FirstCell As Range Dim RowCount...If Not RecordRange Is Nothing Then FirstAddress = RecordRange.Address RowCount..., 0) =FirstCell(1, 1) Results.List(RowCount, 1) = FirstCell(1,2) Results.List...(RowCount, 2) =FirstCell(1, 3) Results.List(RowCount, 3) =FirstCell(1, 4)...RowCount = RowCount + 1 ' 查找下一个匹配项 Set RecordRange =.FindNext(RecordRange
WHERE c_gcode IN ('000001','000002','000003') FOR UPDATE OF c_price OPEN update_gdsstore DECLARE @ROWCOUNT...INT SET @rowcount=1 FETCH ABSOLUTE @rowcount FROM update_gdsstore UPDATE dbo.tb_gdsstore SET c_price...='12' WHERE CURRENT OF update_gdsstore SET @ROWCOUNT=@ROWCOUNT+1 FETCH NEXT FROM update_gdsstore UPDATE...dbo.tb_gdsstore SET c_price='11' WHERE CURRENT OF update_gdsstore SET @ROWCOUNT=@ROWCOUNT+1 FETCH NEXT
Integer pageCurrent = 1; /** 页面大小 */ private Integer pageSize = 10; /** 总行数(通过查询获得) */ private Integer rowCount...setPageSize(Integer pageSize) { this.pageSize = pageSize; } public Integer getRowCount() { return rowCount...; } public void setRowCount(Integer rowCount) { this.rowCount = rowCount; } public Integer getPageCount...() { pageCount = rowCount / pageSize; if (rowCount % pageSize !...=” + rowCount + “, pageCount=” + pageCount + “, records=” + records + “]”; } } Controller层方法: @RequestMapping
@intEnd int Declare @SQl nvarchar(max), @WhereR nvarchar(max), @OrderBy nvarchar(max) set @rowcount...) order by colstat desc end set @OrderBy=' order by '+@PKName+' asc' end set @SQl='SELECT @rowcount...count(*) from '+cast(@TableName as nvarchar(3000))+' where 1=1 '+@WhereR exec sp_executeSql @SQl,N'@rowcount...int output',@rowcount output if @PageIndex=0 and @PageSize=0 --不进行分页,查询所有数据列表 begin set @SQl...return @rowcount -------------------------------------------- --print @SQl --exec [SelectBase] 1,8,
:calculate the bytes32 array's length li_rowcount = li_paralength/32; li_temp...= li_paralength%32; if (li_temp > 0 ) li_rowcount = li_rowcount +1;...//li_sum :the total bytes amount of bytes32 array lbt_result32 = new bytes32[](li_rowcount...); li_sum = li_rowcount *32; li_colidx = 0; for (uint p = 1;p<=...= li_paralength%32; if (li_temp > 0 ) li_rowcount = li_rowcount +1;
=row.count Redim Value(RowCount+1,tbl1.ValueColumnCount+2)'重定义数值数组,存储时间、数值。...+1,tbl1.ValueColumnCount+2))= Value .Cells(RowCount+2,1)="导出人:" .Cells(RowCount+2,2)=HMIRuntime.Tags...("@CurrentUserName").Read .Cells(RowCount+3,1)="导出位置:" .Cells(RowCount+3,2)=HMIRuntime.Tags("@LocalMachineName...").Read .Cells(RowCount+4,1)="导出时间:" .Cells(RowCount+4,2)=Now .Cells(RowCount+5,1)="数据库:"....Cells(RowCount+5,2)=HMIRuntime.Tags("@DatasourceNameRT").Read .Cells(RowCount+6,1)="软件版本:" .Cells
该查询返回%ROWCOUNT为1。...,"Rowcount:",rset....该查询返回%ROWCOUNT为0。...,"Rowcount:",rset....,"Rowcount:",rset.
; $stmt->execute(['kkk','666','k6']); $rowCount = $stmt->rowCount(); echo $rowCount, PHP_EOL; // 1 $id...; $stmt->execute(['ccc','cccc']); $rowCount = $stmt->rowCount(); echo $rowCount, PHP_EOL; // 25 $stmt...; $stmt->execute(['ccc','cccc']); $rowCount = $stmt->rowCount(); echo $rowCount, PHP_EOL; // 0 $stmt...; $stmt->execute(['ddd']); $rowCount = $stmt->rowCount(); echo $rowCount, PHP_EOL; // 11 $stmt = $pdo...; $stmt->execute(['ddd']); $rowCount = $stmt->rowCount(); echo $rowCount, PHP_EOL; // 0 更新和删除操作在数据不存在
This operation may take a LONG time (Run '$HADOOP_HOME/bin/hadoop jar hbase.jar rowcount' to run a counting...2、Scan操作获取数据条数 通过Java API的方式,使用scan进行全表扫描,循环计数RowCount,速度较慢!但快于第一种count方式!...基本代码如下: public void rowCountByScanFilter(String tablename){ long rowCount = 0; try {...+= result.size(); } stopWatch.stop(); System.out.println("RowCount: " + rowCount...Table注册了Coprocessor之后,在执行AggregationClient的时候,会将RowCount分散到Table的每一个Region上,Region内RowCount的计算,是通过RPC
SQL%ROWCOUNT 在执行任何DML语句之前,SQL%ROWCOUNT的值都是NULL,对于SELECT INTO语句,如果执行成功,SQL%ROWCOUNT的值为,如果没有 成功,SQL%...ROWCOUNT的值为,同时产生一个异常NO_DATA_FOUND。...>= 0 THEN --判断更新前SQL%ROWCOUNT的属性 DBMS_OUTPUT.PUT_LINE('SQL%ROWCOUNT value is ' || SQL%ROWCOUNT ||...'before updated'); ELSE DBMS_OUTPUT.PUT_LINE('SQL%ROWCOUNT value is NULL before updated'); END...|| ' rows by SQL Cursor'); --判断SQL%ROWCOUNT的属性 END; Enter value for no: 10 --下面是成功更新后的结果 SQL%ROWCOUNT
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