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BLE(CC2540)
sqlserver 将多个字段合并成一个字段
1.字段为竖向显示的时候在这里我们合并sqr,将id为(47,50,51)合并SELECTname=((stuff((SELECT','+CAST(a.sqrASVARCHAR)FROMformta
ble
_main
chtholl
·
2025-07-08 05:21
sqlserver学习
sql
数据库
java
响应式编程入门教程第二节:构建 Observa
ble
Property<T> — 封装 ReactiveProperty 的高级用法
-CSDN博客响应式编程入门教程第二节:构建Observa
ble
Property<T>—封装ReactiveProperty的高级用法-CSDN博客在上一篇中,我们详细探讨了UniRx的核心组件ReactiveProperty
枯萎穿心攻击
·
2025-07-08 05:20
开发语言
unity
c#
游戏引擎
sql更新某个字段的值为两个字段拼接
//name=name+id;字段后拼接:结果为nameidupdatet_ta
ble
setname=concat(name,id);//name=id+name;字段前拼接:结果为idnameupdatet_ta
ble
setname
·
2025-07-08 05:20
Oracle数据库对象与模式设计
Oracle提供了丰富的数据库对象支持复杂业务场景,包括:表结构与完整性约束索引类型选择与性能调优视图、序列、同义词等辅助对象分区表提升查询效率一、表结构与约束1.创建表(CREATETA
BLE
)与数据类型
·
2025-07-08 05:20
SQL多个字段拼接组合成新字段的常用方法
下面是几种常见的方法:一、CONCAT()函数SELECTCONCAT(column1,column2)ASconcatenated_columnFROMyour_ta
ble
;二、“||”运算符SELECTcolumn1
m0_74823878
·
2025-07-08 04:19
sql
数据库
oracle
SQL某个字段的所有值都拼接一个值
某个字段的所有值都拼接一个值updateta
ble
Name(表名)set"字段"=RTRIM(字段)||'(增加的值)'WHEREtype='0'比如(user表):idnamegender1张三男2玛丽亚女
·
2025-07-08 04:18
【LeetCode 热题 100】48. 旋转图像——转置+水平翻转
Pro
ble
m:48.旋转图像题目:给定一个n×n的二维矩阵matrix表示一个图像。请你将图像顺时针旋转90度。你必须在原地旋转图像,这意味着你需要直接修改输入的二维矩阵。
xumistore
·
2025-07-08 04:48
LeetCode
leetcode
算法
职场和发展
java
sql USING 简化 JOIN 操作
与传统的ON子句相比,USING提供了更简洁的语法1.基本语法与作用ta
ble
1JOINta
ble
2USING(column_name);将ta
ble
1和ta
ble
2中column_name值相同的行连接在一起例
best_virtuoso
·
2025-07-08 04:17
sql
sql
数据库
机器学习笔记二-回归
1.回归的基本概念:自变量(IndependentVaria
ble
):也称为预测变量、解释变量,是模型中的输入变量,用于预测或解释因变量的变化。因变量(Dependent
·
2025-07-08 04:46
MybatisPlus - QueryMapper分页查询出来total=0
是正常的,但是total为0,未能正常分页、是因为、SpirngBoot没有读取到PaginationInnerInterceptor这个Bean解决办法:新建一个MybatisPlasConfig@Ena
ble
TransactionManagement
BACKLS
·
2025-07-08 04:15
java
mysql
数据库
mybatis
spring
boot
ASP.NET Core vs ASP.NET:架构革命与性能飞跃的终极指南——从0到1的8大秘诀!
ASP.NET的“城堡”式架构//旧版ASP.NETWebForms典型结构publicclassGlobal:HttpApplication{voidApplication_Start(){RouteTa
ble
.Routes.Add
墨夶
·
2025-07-08 03:06
C#学习资料
asp.net
架构
后端
Unreal Engine使用Groom 打包后报错
UnrealEngine使用Groom打包后报错版本5.4.4
ble
nder4.2.1项目头发用了groom,运行后报错错误:Assertionfailed:Offset+BytesToRead=0[File
·
2025-07-08 01:23
程序代码篇---Python指明函数参数类型
基本返回类型2.无返回值(None)3.返回多个值(Tuple)4.生成器(Generator)三、高级类型提示用法1.类型别名(TypeAliases)2.泛型(Generics)3.可调用对象(Calla
ble
·
2025-07-08 01:52
Xbox One 控制器转换为 macOS HID 设备的工作原理分析
XboxOne控制器转换为macOSHID设备的工作原理分析源代码在https://github.com/guilhermearaujo/xboxonecontrollerena
ble
r.git这个工程的核心功能是将
aerror
·
2025-07-08 01:52
xbox
macos
查看mysql表_mysql怎么查看表
mysql中查看表的方法:1、查看当前数据库中的表SHOWTA
BLE
S;2、查看表结构showcolumnsfrom表名;show命令可以提供关于数据库、表、列,或关于服务器的状态信息。
碃凡瑶
·
2025-07-08 01:49
查看mysql表
python笔记-Selenium谷歌浏览器驱动下载
Selenium谷歌浏览器驱动下载地址:https://googlechromelabs.github.io/chrome-for-testing/#sta
ble
下面是遇到的问题:python网络爬虫技术中使用谷歌浏览器代码
hero.zhong
·
2025-07-08 00:49
python
笔记
selenium
VTK着色器Mar
ble
Shader代码学习(4)
代码链接https://examples.vtk.org/site/Cxx/Shaders/Mar
ble
Shader/这段代码是一个使用VTK(VisualizationToolkit)实现的复杂着色器渲染示例
点PY
·
2025-07-07 23:06
三维渲染
着色器
学习
如何在YashanDB中实现数据分区管理
数据分区技术通过将大型表拆分成smallermanagea
ble
units(即分区),为查询、更新和维护提供了更高效的操作机制。本文将深入探讨如何在YashanDB数据库中实现有效的数据分区管理。
·
2025-07-07 23:57
数据库
231转序和321转序的姿态角与四元数的变换关系(文末附VC++代码和Matlab验证代码)
这两种转下的姿态角与四元数的转换关系如下:321转序//--------惯性坐标系到箭体系的四元数--------------------//dou
ble
sic_T=sin(Theta_T_rad/2.0
小亨GNC颐园
·
2025-07-07 22:02
matlab
VC++
运载火箭
321转序
231转序
导弹
导航初始化
宽带有哪几种接入方式
question/1025089.html目前的家庭接入方式主要有三种:一是普通电话线的非对称数字用户环路技术(ADSL)方式、二是基于光纤IP网的FTTB+LAN技术方式(小区宽带),三是有线电视的Ca
ble
Modem
weixin_30252709
·
2025-07-07 21:49
flex布局原理以及各属性详解
1布局原理1.1flex是flexi
ble
Box的缩写,意为“弹性布局”,用来为盒状模型提供最大的灵活性,任何一个容器都可以指定为flex布局*当我们为父盒子设为flex布局以后,子元素的float、clear
卷尾猫
·
2025-07-07 20:18
css
css
css3
flexbox
flex
解决org.springframework.http.converter.HttpMessageNotWrita
ble
Exception: Could not write JSON...问题
报错如下:Resolved[org.springframework.http.converter.HttpMessageNotWrita
ble
Exception:CouldnotwriteJSON:(wasjava.lang.NullPointerException
码不停蹄的玄黓
·
2025-07-07 20:12
spring
boot
json
undo ta
ble
space的恢复, database能不关闭最好不要关闭
EnterpriseManagerforOracleDatabase-Version9.2.0.1to11.2.0.4Informationinthisdocumentappliestoanyplatform.PurposePro
ble
mDescription
jnrjian
·
2025-07-07 17:00
oracle
数据库
Oracle 12C 在线移动datafile 不需要归档模式! 只要在线就行
GoalInthisrelease,adatafilecannowbemovedonlinewhileitisopenandbeingaccessed,evenfordatafilesinsystemta
ble
space.Beinga
ble
tomoveadatafileonlinemeansthatmanymaintenanceoperations
·
2025-07-07 17:59
牛顿迭代法求解平方根
一个实例迭代简介牛顿迭代法牛顿迭代法简介简单推导泰勒公式推导延伸与应用一个实例//java实现的sqrt类和方法publicclasssqrt{publicstaticdou
ble
sqrt(dou
ble
n
Young_Gy
·
2025-07-07 17:29
TDengine DECIMAL 数据类型使用手册
相比于浮点数类型(FLOAT、DOU
BLE
),DECIMAL类型:优势:保证精确计算,避免浮点数舍入误差劣势:计算性能相对较低2.基本概念2.1核心术语DECIMA
TDengine (老段)
·
2025-07-07 17:26
TDengine
产品设计
tdengine
大数据
时序数据库
数据库
物联网
涛思数据
iot
陈强《计量经济学及Stata应用》学习笔记——持续更新
1导论1.1什么是计量经济学econometrics几种关系:相关关系、因果关系、逆向因果关系reversecausality、双向因果关系被解释变量dependentvaria
ble
解释变量explanatoryvaria
ble
WangSoooCute
·
2025-07-07 16:23
学习
笔记
无人机三轴稳定化控制(1)____飞机的稳定控制逻辑
Directstickmixingfunctionalityhasbeenremoved,soasnottoremoveallstickmixingfromtheusercompletely//theolddirectoptionisnowusedtoena
ble
fb
森焱森
·
2025-07-07 15:47
算法
c语言
无人机
单片机
.eslintrc.js文件内容/配置eslint/eslint参数
首先放一个官网的链接Listofavaila
ble
rules-ESLint中文文档然后直接上代码这里以vue项目为例,主要两个文件,1是.eslintrc.js文件(配置),2是.eslintignore
是泡沫呀
·
2025-07-07 15:10
前端工程化
javascript
前端
vue.js
webpack
npm
冒泡排序算法详解(含Python代码实现)
冒泡排序(Bub
ble
Sort)是最基础的排序算法之一,通常用于学习排序算法的入门理解。本文将通过Python代码实现冒泡排序,并详细讲解其原理、执行流程、复杂度分析及适用情况。
算法_小学生
·
2025-07-07 14:05
算法
浅析Nordic nRF5 SDK例程架构(三)
浅析NordicnRF5SDK例程架构第一章前言及bsp例程浅析第二章
ble
_app_uart例程浅析第三章添加电池电量服务(BAS)第四章如何使用的修改协议栈(以SESIDE为例)文章目录浅析NordicnRF5SDK
Real你老王
·
2025-07-07 13:01
单片机
c#
浅析Nordic nRF5 SDK例程架构(四)
浅析NordicnRF5SDK例程架构第一章前言及bsp例程浅析第二章
ble
_app_uart例程浅析第三章添加电池电量服务(BAS)第四章如何使用的修改协议栈(以SESIDE为例)文章目录浅析NordicnRF5SDK
Real你老王
·
2025-07-07 13:01
架构
[netty5: FastThreadLocal]-源码解析
ThreadpublicclassThreadimplementsRunna
ble
{//线程局部变
·
2025-07-07 13:30
ARMv8 创建1、2、3级页表代码与注释
对下面的地址空间创建3级页表//level1ta
ble
,4entries://00000000-3FFFFFFF,1GBblock,DDR//40000000-7FFFFFFF,1GBblock,DDR
liuluyang530
·
2025-07-07 13:29
armv8
mmu
页表
ARMv8 创建3级页表示例
最近在研究armv8页表创建过程,顺带做了一个如下形式的页表,//level1ta
ble
,4entries://00000000-3FFFFFFF,1GBblock,DDR//40000000-7FFFFFFF
liuluyang530
·
2025-07-07 13:29
FPGA验证
ARMv8
armv8
页表
mmu
浅析Nordic nRF5 SDK例程架构(二)
浅析NordicnRF5SDK例程架构第一章前言及bsp例程浅析第二章
ble
_app_uart例程浅析第三章添加电池电量服务(BAS)第四章如何使用的修改协议栈(以SESIDE为例)文章目录浅析NordicnRF5SDK
Real你老王
·
2025-07-07 12:25
架构
单片机
嵌入式硬件
【机器学习笔记 Ⅱ】10 完整周期
机器学习的完整生命周期(End-to-EndPipeline)机器学习的完整周期涵盖从问题定义到模型部署的全过程,以下是系统化的步骤分解和关键要点:1.问题定义(Pro
ble
mDefinition)目标
·
2025-07-07 12:24
【XML笔记】XML入门_XML文档的创建
一.XML1.概述:XML是Extensi
ble
MarkupLanguage可扩展标记语言是SGML(标准通用化标记语言)的一个子集,用于提供数据描述格式,适用于不同应用程序间的数据交换,这种交换不以预先定义的数据结构为前提
追云的帆
·
2025-07-07 10:38
JavaWeb
xml
文档
oracle操作xml笔记
第一个例子创建表:CREATETA
BLE
xml_ta
ble
(idNUMBERPRIMARYKEY,xml_dataXMLType);插入数据:INSERTINTOxml_ta
ble
(id,xml_data
chushiyunen
·
2025-07-07 10:38
oracle
xml
笔记
java并发编程--可见性、原子性、有序性
在Java中,对基本数据类型(除long和dou
ble
在某些平台上)的简单读写操作是原子的,但像i++这样的复合操作不是原子的。示例:publicclassAtomicityExa
weixin_ab
·
2025-07-07 09:59
jvm
jvm
Vue3+Vite+TypeScript+Element Plus开发-22.客制Ta
ble
组件
系列文档目录Vue3+Vite+TypeScript安装ElementPlus安装与配置主页设计与router配置静态菜单设计Pinia引入Header响应式菜单缩展Mockjs引用与Axios封装登录设计登录成功跳转主页多用户动态加载菜单Pinia持久化动态路由-动态增加路由动态路由-动态删除路由路由守卫-无路由跳转404路由守卫-未登录跳转登录界面登录退出Tags-组件构建Tags-与菜单联动
秋之猫
·
2025-07-07 09:58
Plus开发
vue.js
按钮组件
表组件
vue3
vite
element
plus
如何实现表格选中时禁用树结构的复选框功能(El-Tree 与 El-Ta
ble
联动实现)
使用ElementUI的el-tree和el-ta
ble
组件,我们可以实现当表格中有选中行时,自动禁用树结构中的复选框,反之亦然。这不仅提升了用户体验,还能有效防止数据操作上的冲突。
Peak_Gao
·
2025-07-07 09:28
vue.js
elementui
javascript
基于 Vue3 + Element-plus 封装的 Ta
ble
组件
项目信息项目名称:vue3-xmw-ta
ble
预览地址:点击预览Github:vue3-element-ta
ble
使用方法根目录下执行npmivue3-xmw-ta
ble
命令npmivue3-xmw-ta
ble
白雾茫茫丶
·
2025-07-07 09:57
前端开发
前端
vue.js
elementui
element ui表格data搜索重置功能
elementui表格搜索重置功能本地1.html搜索重置...2.datadata(){return{ta
ble
data:[{name:1,id:1},{name:2,id:2}],//你的数据ta
ble
data2
q249859693
·
2025-07-07 09:57
elementui
vue.js
前端
`useDetailLoader` 组合函数封装(支持自动加载 + 页面判断 + 防重复)
或指定字段)✅只在指定页面名称时才触发(避免跳转到其他页面时误触发)✅避免同一id重复加载✅支持初始加载和浏览器返回场景✅支持动态更新loading状态useDetailLoader.ts//composa
ble
s
JaysonJin
·
2025-07-07 08:53
前端
javascript
开发语言
SVG格式深度解析与Path应用实战:从原理到企业级全场景开发(实战版)
一、简介在数字图形领域,SVG(Scala
ble
VectorGraphics)凭借其矢量特性、可编辑性和交互能力,成为现代设计和开发的核心工具。
·
2025-07-07 08:48
Gradio全解13——MCP详解(2)——MCP能力协商与通信机制
章MCP详解13.2MCP能力协商与通信机制13.2.1能力协商机制与消息规范1.能力协商机制2.消息规范及错误码13.2.2MCP通信机制1.协议层四种方法2.传输层机制:Stdio与Streama
ble
HTTP3
·
2025-07-07 07:15
网络通信协议与虚拟网络技术相关整理(上)
#作者:程宏斌文章目录tcp协议udp协议arp协议icmp协议dhcp协议BGP协议OSPF协议BGPvsOSPF对比表VLAN(VirtualLAN)VXLAN(VirtualExtensi
ble
LAN
·
2025-07-07 07:45
Feign 解码异常处理:解决 No Suita
ble
HttpMessageConverter 问题
问题场景与错误解析在使用SpringCloudFeign进行微服务间通信时,常遇到以下典型错误:feign.codec.DecodeException:Couldnotextractresponse:nosuita
ble
HttpMessageConverterfoundforresponsetype
码傻啦弟
·
2025-07-07 07:43
软件开发
java
开发语言
Feign
spring
boot
Libigl在编译时常见错误与解决方法
igl_core错误C2001常量中有换行符igl_core错误C2001常量中有换行符igl_core错误LNK1104无法打开文件“…\lib\Debug\igl.lib”405_AsRigidAsPossi
ble
hunjinYang
·
2025-07-07 06:12
C++库配置
windows
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