previewstatement（pb中数据库表的结构在哪个表）

本文目录

• pb中数据库表的结构在哪个表
• Previewstatement是什么意思
• 求电脑系统里常用的英文单词
• sql 数据库中如何录入图像
• class+room=classroom这列词汇还有哪些
• ·(急啊~~)基于SQL、ASP、Dreamweaver的论文外文翻译
• 急用啊！！！！！！elias’ story的全文！！！！！
• statement, 是什么意思

pb中数据库表的结构在哪个表

PowerBuilder是目前公认的、最佳的数据库前端开发工具之一。在实际开发应用中，经常会遇到修改数据库表结构的情况。用PowerBuilder修改数据库表结构与用Foxbase修改数据库结构不同。在PowerBuilder中，除可以在数据库表结构中添加字段名外，无法直接修改数据库表结构，如删除某个字段名或类型或字段名长度等，都会导致数据库表记录的丢失。我们通过实践探索，总结了几种方法仅供大家参考，请大家批评指正。一、 修改数据库表结构，数据库表中没有记录方法1:将表结构以Export Table 文件格式输出。从Database中选择要修改的数据库表Table。从Objects中选择Export Table/View Syntax to Log，取名保存即选Save Log As，以*.sql格式保存。从Objects中选择Database Administration。从File中选择Dos Open，选文件名File name，*.sql，打开进行修改。从Objects中选择Execute　SQL。即产生一新的数据库表结构。注意:Table名不要同名。方法2:将表结构以SQL Syntax 文件格式输出。从Database中选择要修改的数据库表Table。按Preview键。从File中选择Save Rows as，File Format 选SQL Syntax，取表名*.sql保存。从File中选择Dos Open，打开表名*.sql，进行修改。取表名后，Execute　SQL。注意:此种方法没有生成Primary Key。二、 修改数据库表结构，保存原数据库表中记录方法1:先修改数据库表结构，用SQL语句转移数据库表中记录将表1生成表1.sql，修改结构，将表1另取名为表2。运行表2.sql，生成表2。此时产生一新的数据库表结构。从Objects中选择Database Administration，写SQL Statement: Insert　into 新表名select *　from 旧表名; Execute　SQL。将旧表中所有字段内容转入新表中。删除表1，从File中选择Dos Open，打开文件名File name即表2.sql，将表2统一改为表1.运行表1.sql，生成新结构的表1，此时无记录。按步骤3，将表2中的记录全部转入表1中。若将部分字段转入，写SQL Statement:insert into 新表名(字段1，字段2......)select 字段1，字段2......from 旧表名;Execute　SQL。旧表中部分字段内容转入新表中。方法2:将表结构和记录以SQL Syntax 文件格式输出。从Database中选择要修改的数据库表Table，按Preview键。从File中选择Save Rows as，File　Format 选SQL Syntax，取表名*.sql保存。从File中选择Dos Open，打开表名*.sql，进行修改。取表名后，Execute　SQL。方法3:将表结构和记录以TXT 文件格式输出。从Database中打开数据库表，按Preview键。从File中选择Save Rows as，File　Format 选TXT，取表名*.txt保存。将表生成表.sql，修改结构，运行表.sql，此时产生一新的数据库表结构。从Database中打开数据库表，按Preview键。从Rows中选择Import，选*.txt。从File中选择Save changes to Database。注意:方法1适用于任何修改数据库表结构的任何情况。方法2和方法3对删除字段名不适用。另外，用Message传递参数必须注意以下几点:1. 最好执行完窗口操作(打开或关闭)后马上将Message消息对象的值传给变量，这是因为Message是全局使用的对象，每一次事件被触发或传送时都会被使用，其他Script 也有可能用到Message消息对象，因此它有被覆盖的危险。2.避免传送NULL对象，以免程序出错。

Previewstatement是什么意思

Preview statement
预览语句

双语例句
1
Obama called Bush and Clinton to preview his statement, said the senior administration official, who refused to be identified on the call.
白宫这位高级官员说，奥巴马打电话给小布什和克林顿让他们预览一下他的稿子，不过这位官员拒绝在电话中透露自己的身份。

求电脑系统里常用的英文单词

Access
访问
Click
单击
Code
代码
Combo box
组合框
Command
命令
Container
容器
Control
控件
Database
数据库
Destination folder
目标文件夹
display
显示
document.
文档
double-click
双击
drop-down
下拉列表
editor
器
export
导出
field
字段
file
文件
folder
文件夹
form
窗体
form
窗体
format
格式
header
标题
install
安装
macro
宏
menu
菜单
options
选项
prompt
提示
property
属性
query
查询
report
报表
right-click
右键单击
Run mode
运行模式
Save as
另存为
speech
语音
start-up
启动
subform
子窗体
tab
选项卡
tool
工具
toolbar
工具栏
transform
转换
undo
撤消
utility
实用工具
view
视图
voice
声音
wizard
向导
tab
标签
syntax
语法
convert
转换
database
数据库
utilities
实用工具
category
类别
tag
标记
pane
窗格。
setting
设置
account
账户
recipient
收信人
hyperlink
超链接
note
注
field
字段
code
代码
forward
前进（转发）
topic
主题
engine
引擎
navigation
导航
tutorial
教程
general
常规
applied
生效
registry
注册表
editor
器
rename
重命名
minimize
最小化
program
程序
uninstall
卸载
reinstallation
重新安装
maximize
最大化
symptom
故障现象
presentation
演示文稿
slides
幻灯片
media
媒体
animation
动画
default
默认
custom
自定义
quota
配额
prompt
提示
array
阵列
fault-tolerance
数据容错
drive
驱动器
pool
池
mount
安装
failure
故障
integrate
集成
capability
功能
port
端口
public-key
公钥
algorithm
算法
logon
登录
image
映像
VPN
虚拟专用网络
Modular
模块式
Architecture
结构
Modulations
调制
Infrastructure
基础设施
Default
默认
Adapter
卡
Backup
备份
Restore
还原
recovery 数据
Server
服务器
domain
域
controller
控制器
startup
启动
dual-boot
双启动
WAN
广域网
Interface
接口
end-to-end
端到端
solution
解决方案
modem
调制解调器
A wide spectrum of users
不同层次的用户
abstract
摘要
Accessibility
辅助功能
across the organization
跨越整个组织
Activation Wizard
激活向导
Active Directory
Active Directory
Active Directory Populace
Active Directory 移植
add-in
返回页首
administration
管理
Administrative Tool
管理工具
administrator
管理员
affiliation changed
affiliation changed
Agility
敏捷性
All rights reserved
保留所有权利
alternatively
alternatively
analysis
分析
animated
动画的
Animated Tour
动画演示
anticounterfeiting features
防伪特征
anti-piracy technology
反盗版技术
appendix
附录
application development cycle
开发周期
application programming interface (API)
应用程序编程接口 (API)
architecture
体系结构
As Needed
按需
asynchronous
异步
audio output
音频输出
Automated task assignment
自动任务分配
b2b
企业对企业
Backup Device
备份设备
be built into
内置
be provided
自动完成
be referred to
提到的，称为
benefit
优点
Benefits
优越性
Beyond Permissions
超越权限
binding
捆绑
boot disk
启动盘
box
框
browse
浏览
build
创建
business
业务
business need
业务需求
Business Software Alliance (BSA)
商业软件联盟
business value
商业价值
by default
默认时
cache
缓存
Capability
能力
capacity planning
容量规划
capacity planning
容量规划
Capitalize on
利用
case study
案例研究
CD-ROM drive
光驱
check box
复选框
Checklists
核对清单
click
单击
close-talk microphone
近距离麦克风
coauthor
合著者
collaboration
协作
Collaboration Clients
协作客户端程序
command-line
命令行
compare
比较
comparison
对比
compatibility
兼容性
Computer Name
计算机名称
Contact Us
与我们联系
content
内容
conversion
转换
converter
转换器
core business areas investments
核心业务领域投资
creation
创建
Credential
证书
critical insights
关键性的洞察力
cube
多维数据集
Cube Access over the Web
通过 Web 访问多维数据集
customer segment
客户群
customizability
可自定义性
customizable
可自定义
data
数据
data anomalies
数据异常
data usefulness
数据可用性
database
数据库
Database Schema
数据库架构
Data-Driven
由数据驱动
data-type
数据类型
default
默认
default drive letter
默认驱动器符
default value
默认值
delete
删除
deliverable
可交付任务
demonstrations
演示
demos
演示
dependencies
相互依赖性
deployment
部署
Deployment Kit
部署工具包
deployment scenarios
部署情形
desktop
台式机，桌面
developers
开发人员
DHCP Scope
DHCP 范围
diagram
图表
dial-in access
拨号接入
dialog box
对话框
digital dashboard
数字仪表板
digital signature
数字签名
dimension types
维度类型
disk configuration
磁盘配置
disk partitions
磁盘分区
disk storage
磁盘存储
display
显示
Domain Controller
域控制器
double-click
双击
download
下载
drive
促进
drive
驱动器
dynamic Web pages
动态 Web 页
economic chain
经济插件链
editor’s note
编者按
electronic commerce
电子商务
electronic document.interchange
电子文档交换
e-mail performance
电子邮件性能
E-Mail This Page
发送此页
enable
启用
Enforcing
执行
enhancements guide
增强指南
enterprise-wide
企业范围
erase all data
抹掉所有数据
error message
错误消息/信息
exchange
交换
extensible
可扩展
Extensible Markup Language (XML)
可扩展标记语言
extraneous elements
外来因素
Extranet
外部网
features
功能
features
特性
Features List
特性列表
file
文件
file converter
文件转换器
file viewer
文件查看器
floppy disk
软盘
floppy drive
软驱
folder
文件夹
for profit
谋取利益
format
格式，格式化
Free Newsletter
免费新闻快递
Full compatibility
完全兼容
full functionality
全部功能
generate
生成
getting started
入门
Gigabytes
GB，千兆节
graphical analysis
图形分析
graphics rendering
图形显示
handling
手续费
handwriting recognition
手写识别
Hard Disk
硬盘
Hardware Requirements
硬件要求
hash algorithm
hash algorithm
hash value
hash value
hierarchies
hierarchies
higher-baud
更高波特率
higher-resolution
更高分辨率
hosted application service
托管应用程序服务
How-to Article
指导文章
implement
执行
improved
改进
Incompatibilities
不兼容性
in-depth
详尽的
information
信息
information sharing
信息共享
Infrastructure
基础架构
insert
插入
inside out
全面剖析
Instruction
说明
instructor-led
导师辅导
internal effort
内部工作量
interoperability
互操作性
is committed to
承诺
knowledge base
知识库
label
标签
laptop
笔记本电脑
leverage
借鉴
license
许可
license agreement
许可证协议
licensing
授权
line-of-business application
业务线应用程序
list of folders
文件夹列表
log on
登录
logical drive
逻辑驱动器
logo
徽标
managing project
管理项目
manual
手册
Microsoft Authorized Training & Education Centers (ATEC)
微软授权培训教育中心
migration
迁移
Minimum Requirement
最低要求
mobile user
移动用户
modem
调制解调器
monitor
显示器
multimedia
多媒体
native
本机
Network Hub
网络集线器
Network Interface Card
网卡
Newsgroups
新闻组
Online Help
联机帮助
Online Registration
联机注册
ONS Exclusive
ONS 独家报道
operating system
操作系统
optimize performance
优化性能
optimizing performance
性能优化
optional
可选的
ordering
订购
organizational units (OU)
部门 (OU)
overall task performance
整体任务性能
overhaul
检修
overhead
开销
overview
概述
pane
窗格
parameter
参数
parent-child dimensional hierarchies
父子维度层次结构
partition size
分区容量
partitions
分区
password
密码
penetrate and capture new markets
深入市场并夺取新市场
performance
性能
performance indicator
性能指标
performance tuning
性能调整
peripherals
外围设备
Pixels
像素
PKI
PKI
plug-in module
插件模块
point
点
pointing device
指点设备
post
发布，张贴，提交
pre-built
预制
Preferred DNS Server
首选 DNS 服务器
prerequisite
前提
preview
预览
pricing
价格
printer
打印机
Privacy
隐私
Privacy Statement
隐私声明
private network
专用网络
processor
处理器
Product Activation
产品激活
product guide
产品指南
Product Highlights
产品突出特点
product key
产品密钥
product overview
产品概述
professional presentations
专业演示
profile
配置文件
program
程序
programmable buttons
可编程按钮
programming concepts
编程概念
project management
项目管理
project planning
项目规划
project view
项目视图
prominently
醒目
prompt
提示
properties
属性
public standards
公共标准
publish
发布
query
查询
real-time
实时
reboot
重新启动
recipient
收件人
reconfigure
重新配置
reduced functionality
缩减功能
refreshable data
可刷新数据
registration
注册
Remote Access Hardware
远程接入硬件
remote connection
远程连接
remote display protocol
远程显示协议
reside
驻留
restart
重新启动
retail version
零售版
review
审阅
right-click
右击
roaming user
漫游用户
round mouse port
圆形鼠标端口
scalability
可扩展性
scheduling
日程安排
Screen shot
屏幕快照
server
服务器
server configuration
服务器配置
server-side components
服务器端组件
setup wizard
安装向导
share
共享
sharing
共享
shipping
运费
shortcuts
快捷方式
slow-link
慢速链接
smart tag
智能标记
SmartCard
SmartCard
snap-in
管理单元
software piracy
软件盗版
solution
解决方案
sound file
声音文件
source document.
源文档
source file
源文件
special offers
特别优惠
specific
特定的
specifications
规格
specify
指定
speech recognition
语音识别
splash screen
启动画面
spreadsheet
电子表格
stand-alone
单机，独立式
stand-alone policy
单机策略
static
静态的
statistical method
统计方法
status reporting
状态报告
streamline
简化
Subnet mask
子网掩码
sufficient
充足的
suite
套件
System Requirements
系统要求
system usability scale
系统实用性级别
tab
标签
tab
选项卡
tablet form
输入板形式
tap
开辟
Task lists
任务列表
task pane
任务窗格
technical
技术
technical information
技术信息
Terms of Use
使用条款
thin client terminal
瘦客户终端
time-to-market
投入市场所需的时间
timing error
计时错误
tips
提示
tips and trick
提示与技巧
to-do list
待办事宜
toll-free
免费
tool
工具
tour
漫游
tracking
跟踪
Training & Certification
培训和认证
transparent
透明的
trend
趋势
trial software
试用软件
trial version
试用版
tricks
技巧
Tuning
调整
tutorials
教程
type
键入
typical Setting
典型设置
unallocated
未分配的
unveiling
揭幕
update
更新
upgrade
升级
UPS
UPS
user group
用户组
User setting
用户设置
utility
实用程序
utility tool
实用工具
value
值
version
版本
viewer
查看器
virus free
无病毒
Warning
警告
Web component
Web 组件
Web Team Talking
Web 小组论坛
Web Workshop
Web 工作室
white paper
白皮书
Windows Installer package
Windows 安装程序包
workbook
工作簿
workstation
工作站
-previewstatement

sql 数据库中如何录入图像

Dim Constr As String ’ODBC路径
Dim FileName As String ’图片文件名
Const BLOCKSIZE = 4096 ’每次读写块的大小
Dim ADOCon As New ADODB.Connection ’ADODB Connection对象
Dim ADORst As New ADODB.Recordset ’ADODB Recordset 对象
Dim ADOFld As ADODB.Field ’ADODB Field 对象
Private Sub SaveToDB(ByRef Fld As ADODB.Field, DiskFile As String)
Dim byteData() As Byte ’定义数据块数组
Dim NumBlocks As Long ’定义数据块个数
Dim FileLength As Long ’标识文件长度
Dim LeftOver As Long ’定义剩余字节长度
Dim SourceFile As Long ’定义自由文件号
Dim i As Long ’定义循环变量
SourceFile = FreeFile ’提供一个尚未使用的文件号
Open DiskFile For Binary Access Read As SourceFile ’打开文件
FileLength = LOF(SourceFile) ’得到文件长度
If FileLength = 0 Then ’判断文件是否存在
Close SourceFile
MsgBox DiskFile & “无 内 容 或 不 存 在 !“
Else
NumBlocks = FileLength \ BLOCKSIZE ’得到数据块的个数
LeftOver = FileLength Mod BLOCKSIZE ’得到剩余字节数
Fld.Value = Null
ReDim byteData(BLOCKSIZE) ’重新定义数据块的大小
For i = 1 To NumBlocks
Get SourceFile, , byteData() ’ 读到内存块中
Fld.AppendChunk byteData() ’写入FLD
Next i
ReDim byteData(LeftOver) ’重新定义数据块的大小
Get SourceFile, , byteData() ’读到内存块中
Fld.AppendChunk byteData() ’写入FLD
Close SourceFile ’关闭源文件
End If
End Sub

Private Sub Form_Load()
Constr = “DSN=image;UID=SA;PWD=13706001674“ ’定义ODBC连接
ADOCon.Open Constr ’创建一个连接
If ADORst.State 《》 adStateClosed Then ADORst.Close
SQLYZ = “SELECT * FROM Table1“
ADORst.Open SQLYZ, ADOCon, adOpenDynamic, adLockOptimistic
’打开一个ADO动态集 表名为table
Set AdoCtr.Recordset = ADORst ’将动态集赋给ADO控件
End Sub

Private Sub Form_Unload(Cancel As Integer)
’记得关闭打开的数据集，释放资源
ADORst.Close
ADOCon.Close
Set ADORst = Nothing
Set ADOCon = Nothing
End Sub
Private Sub PreView_Click()
’显示打开文件的公用对话框，选择需要加入数据库的图片
CDlg.Filter = “图片文件|*.bmp;*.JPG;*.JPGE;*.JPE“
CDlg.ShowOpen
FileName = CDlg.FileName
PicBox.Picture = LoadPicture(FileName) ’预览图片
End Sub
Private Sub Save_Click()
ADORst.AddNew ’新增纪录
ADORst(“姓名“).Value = Names.Text ’给动态集的第一个字段赋值
ADORst(“编号“).Value = Numb.Text ’给动态集的第二个字段赋值
Set ADOFld = ADORst(“照片“) ’给ADODB.Field对象赋值
Call SaveToDB(ADOFld, FileName)
’调用子程序，给第三个字段（image）赋值
ADORst.Update
End Sub
Private Sub Timer1_Timer()
Names.Text = Date
Numb.Text = Time
End Sub
Private Sub Update_Click()
’重新打开纪录集，刷新纪录
ADORst.Close
ADOCon.Close
Set ADORst = Nothing
Set ADOCon = Nothing
ADOCon.Open Constr
ADORst.Open “table1“, ADOCon, adOpenDynamic, adLockOptimistic
Set AdoCtr.Recordset = ADORst
End Sub
要使用到的控件你看代码就可以了.VB6.0+ADO2.5
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class+room=classroom这列词汇还有哪些

schoolmates,（一）、常见前缀
1． 表示否定意义的前缀
un: unbelievable uncomfortable unconscious unfair uneasy
unlike unknown unusual unexpected unemployment
unfortunately
in: indirect inevitable incorrect incomplete independent
im: impossible impatient impractical impolite
il: illegal
ir: irrespective irregular irresponsible
mis: mistake misunderstand mislead misfortune misconduct
dis: disadvantage discourage disabled disagree disapprove
discount discover disappear disorder
non: nonsense non-smoking
ab: abuse
anti: anti-Japanese anti-smoking
2． 表示时间、序列的前缀
pre (前，预先): preview preschool prehistory previous
post (后): postwar postgraduate
pro (向前): proceed progress prolong
re (回，再): review recycle react reproduce
recover reform refresh renew restore
3． 表示方向、位置的前缀
inter (在…之间): international interact interview internet
in/im (向内): internal indoor inside interior
import immigrate
ex (向外): export exterior external exceed
under (在下面): underestimate underground underline undergraduate
trans (横过、): transport transplant transform transmit
out (外): outdoor outwards outside
mid (在中间): midnight midday mid-term
4． 表示数量、大小的前缀
uni (一，统一): unique unite unity universal uniform
min (少，减): minor minus minimum
multi (多): multiply multinational multiple
5． 动词性前缀
en: enable enjoy enforce encourage
（二）、常见后缀
1． 常见名词后缀：
ness: weakness illness fitness happiness
ment: treatment statement argument arrangement equipment
management development employment improvement achievement
punishment measurement replacement
ion: invention selection suggestion election education
prevention reflection radiation rejection reaction
instruction distinction devotion innovation attraction
expression impression
tion: intention attention
sion: expansion explosion decision extension collision
ation: invitation realization imagination modernization obligation
foundation determination reservation industrialization application
ship: friendship scholarship ownership relationship hardship
leadership (人):
ity: popularity quality maturity personality publicity
security diversity
dom: freedom wisdom
age: storage package postage marriage shortage
al: refusal removal arrival proposal survival approval
ism: tourism organism criticism
y: discovery recovery injury difficulty delivery
ure: failure pressure exposure departure
ence: difference patience independence absence evidence confidence
ance: distance significance resistance importance ignorance
ist (人): tourist scientist specialist
ant (人): servant immigrant applicant assistant accountant
consultant defendant inhabitant
ian (人): technician musician electrician
or (人): survivor operator inventor governor conductor competitor
er (人): manufacturer consumer customer owner prisoner employer
2． 常见形容词后缀：
ful (充满…的): faithful fearful hopeful fruitful helpful respectful
graceful painful cheerful thoughtful powerful
y (…的): wealthy thirsty worthy hasty lucky noisy faulty
less (无…的): hopeless useless worthless restless helpless meaningless
al (…的): national original practical natural musical occasional
medical formal personal professional experimental
able (能…的、可…的): suitable valuable respectable remarkable
favorable reliable profitable fashionable miserable
noticeable portable reasonable honorable preferable
desirable acceptable comparable comfortable
ly (…的): timely friendly deadly costly
ic (…的): symbolic heroic classic historic organic
ial (…的) : industrial racial commercial beneficial financial influential
ive (…的): respective effective impressive expensive progressive attractive
protective comparative
ious (…的): suspicious mysterious
ous (…的): poisonous humorous dangerous
ish (似…的): childish foolish bookish
ent: different patient independent absent evident confident
ant: distant significant resistant important ignorant
（三）、合成词
gentleman hometown homework housework mankind
Second-hand earthquake playground mainland widespread
spacecraft Postcard Postman taxpayer wildlife
mailbox supermarket Headline deadline timetable
football Pastime hardware spaceship stockholder
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·(急啊~~)基于SQL、ASP、Dreamweaver的论文外文翻译

SQL (sometimes expanded as Structured Query Language) is a computer language used to create, retrieve, update and delete data from relational database management systems. SQL has been standardized by both ANSI and ISO.
SQL is commonly spoken either as the names of the letters ess-cue-el (IPA: ). The official pronunciation of SQL according to ANSI is ess-cue-el. However, each of the major database products (or projects) containing the letters SQL has its own convention: MySQL is officially and commonly pronounced “My Ess Cue El“; PostgreSQL is expediently pronounced postgres (being the name of the predecessor to PostgreSQL); and Microsoft SQL Server is commonly spoken as Microsoft-sequel-server.
History
An influential paper, A Relational Model of Data for Large Shared Data Banks, by Dr. Edgar F. Codd, was published in June 1970 in the Association for Computing Machinery (ACM) journal, Communications of the ACM, although drafts of it were circulated internally within IBM in 1969. Codd’s model became widely accepted as the definitive model for relational database management systems (RDBMS or RDMS).
During the 1970s, a group at IBM’s San Jose research center developed a database system “System R“ based upon Codd’s model. Structured English Query Language (“SEQUEL“) was designed to manipulate and retrieve data stored in System R. The acronym SEQUEL was later condensed to SQL because the word ’SEQUEL’ was held as a trademark by the Hawker Siddeley aircraft company of the UK. Although SQL was influenced by Codd’s work, Donald D. Chamberlin and Raymond F. Boyce at IBM were the authors of the SEQUEL language design. Their concepts were published to increase interest in SQL.
The first non-commercial, relational, non-SQL database, Ingres, was developed in 1974 at U.C. Berkeley.
In 1978, methodical testing commenced at customer test sites. Demonstrating both the usefulness and practicality of the system, this testing proved to be a success for IBM. As a result, IBM began to develop commercial products based on their System R prototype that implemented SQL, including the System/38 (announced in 1978 and commercially available in August 1979), SQL/DS (introduced in 1981), and DB2 (in 1983).
At the same time, Relational Software, Inc. (now Oracle Corporation) saw the potential of the concepts described by Chamberlin and Boyce and developed their own version of a RDBMS for the Navy, CIA and others. In the summer of 1979, Relational Software, Inc. introduced Oracle V2 (Version2) for VAX computers as the first commercially available implementation of SQL. Oracle V2 beat IBM’s release of the System/38 to the market by a few weeks.
Standardization
SQL was adopted as a standard by ANSI (American National Standards Institute) in 1986 and ISO (International Organization for Standardization) in 1987. However, since the dissolution of the NIST data management standards program in 1996 there has been no certification for compliance with the SQL standard so vendors must be relied on to self-certify.
The SQL standard is not freely available. SQL:2003 and SQL:2006 may be purchased from ISO or ANSI. A late draft of SQL:2003 is available as a zip archive from Whitemarsh Information Systems Corporation. The zip archive contains a number of PDF files that define the parts of the SQL:2003 specification.
Scope
SQL is designed for a specific purpose: to query data contained in a relational database. SQL is a set-based, declarative programming language, not an imperative language such as C or BASIC.
Language extensions such as Oracle Corporation’s PL/SQL bridge this gap to some extent by adding procedural elements, such as flow-of-control constructs. Another approach is to allow programming language code to be embedded in and interact with the database. For example, Oracle and others include Java in the database, and SQL Server 2005 allows any .NET language to be hosted within the database server process, while PostgreSQL allows functions to be written in a wide variety of languages, including Perl, Tcl, and C.
Extensions to and variations of the standards exist. Commercial implementations commonly omit support for basic features of the standard, such as the DATE or TIME data types, preferring variations of their own. SQL code can rarely be ported between database systems without major modifications, in contrast to ANSI C or ANSI Fortran, which can usually be ported from platform to platform without major structural changes.
PL/SQL, IBM’s SQL PL (SQL Procedural Language) and Sybase / Microsoft’s Transact-SQL are of a proprietary nature because the procedural programming language they present are non-standardized.
Reasons for lack of portability
There are several reasons for this lack of portability between database systems:
* The complexity and size of the SQL standard means that most databases do not implement the entire standard.
* The standard does not specify database behavior in several important areas (e.g. indexes), leaving it up to implementations of the database to decide how to behave.
* The SQL standard precisely specifies the syntax that a conforming database system must implement. However, the standard’s specification of the semantics of language constructs is less well-defined, leading to areas of ambiguity.
* Many database vendors have large existing customer bases; where the SQL standard conflicts with the prior behavior of the vendor’s database, the vendor may be unwilling to break backward compatibility.
SQL keywords
Queries
The most common operation in SQL databases is the query, denoted with the SELECT keyword. SQL SELECT queries are declarative:
* SELECT retrieves data from tables in a database. While often grouped with Data Manipulation Language statements, SELECT is considered by many to be separate from SQL DML. SELECT queries allow the user to specify a description of the desired result set, but it is left to the devices of the database management system (DBMS) to plan, optimize, and perform the physical operations necessary to produce that result set. A SQL query includes a list of columns to be included in the final result immediately following the SELECT keyword. An asterisk (“*“) can also be used as a “wildcard“ indicator to specify that all available columns of a table (or multiple tables) are to be returned. SELECT is the most complex statement in SQL, with several optional keywords and clauses:
o The FROM clause indicates the source tables from which the data is to be drawn. The FROM clause can include optional JOIN clauses to join related tables to one another.
o The WHERE clause includes a comparison predicate, which is used to narrow the result set. The WHERE clause eliminates all rows from the result set for which the comparison predicate does not evaluate to True.
o The GROUP BY clause is used to combine rows with related values into elements of a smaller set of rows.
o The HAVING clause is used to identify which of the “combined rows“ (combined rows are produced when the query has a GROUP BY clause or when the SELECT part contains aggregates), are to be retrieved. HAVING acts much like a WHERE, but it operates on the results of the GROUP BYand can include aggregate functions.
o The ORDER BY clause is used to identify which columns are used to sort the resulting data. Unless an ORDER BY clause is included, the order of rows returned by SELECT is never guaranteed.
Data retrieval is very often combined with data projection; usually it isn’t the verbatim data stored in primitive data types that a user is looking for or a query is written to serve. Often the data needs to be expressed differently from how it’s stored. SQL allows a wide variety of formulas included in the select list to project data.
Example 1:
SELECT * FROM books
WHERE price 》 100.00
ORDER BY title
This is an example that could be used to get a list of expensive books. It retrieves the records from the books table that have a price field which is greater than 100.00. The result is sorted alphabetically by book title. The asterisk (*) means to show all columns of the books table. Alternatively, specific columns could be named.
Example 2:
SELECT books.title, count(*) AS Authors
FROM books
JOIN book_authors
ON books.book_number = book_authors.book_number
GROUP BY books.title
which could also be written as
SELECT title, count(*) AS Authors
FROM books NATURAL JOIN book_authors
GROUP BY title
under the precondition that book_number is the only common column name of the two tables and that a column named title only exists in books.
Example 2 shows both the use of multiple tables in a join, and aggregation (grouping). This example shows how many authors there are per book. Example output may resemble:
Title Authors
---------------------- -------
SQL Examples and Guide 3
The Joy of SQL 1
How to use Wikipedia 2
Pitfalls of SQL 1
How SQL Saved my Dog 1
Data manipulation
First, there are the standard Data Manipulation Language (DML) elements. DML is the subset of the language used to add, update and delete data:
* INSERT is used to add rows (formally tuples) to an existing table.
* UPDATE is used to modify the values of a set of existing table rows.
* MERGE is used to combine the data of multiple tables. It is something of a combination of the INSERT and UPDATE elements. It is defined in the SQL:2003 standard; prior to that, some databases provided similar functionality via different syntax, sometimes called an “upsert“.
* DELETE removes zero or more existing rows from a table.
INSERT Example:
INSERT INTO my_table (field1, field2, field3) VALUES (’test’, ’N’, NULL);
UPDATE Example:
UPDATE my_table SET field1 = ’updated value’ WHERE field2 = ’N’;
DELETE Example:
DELETE FROM my_table WHERE field2 = ’N’;
Transaction controls
Transactions, if available, can be used to wrap around the DML operations:
* BEGIN WORK (or START TRANSACTION, depending on SQL dialect) can be used to mark the start of a database transaction, which either completes completely or not at all.
* COMMIT causes all data changes in a transaction to be made permanent.
* ROLLBACK causes all data changes since the last COMMIT or ROLLBACK to be discarded, so that the state of the data is “rolled back“ to the way it was prior to those changes being requested.
COMMIT and ROLLBACK interact with areas such as transaction control and locking. Strictly, both terminate any open transaction and release any locks held on data. In the absence of a BEGIN WORK or similar statement, the semantics of SQL are implementation-dependent.
Example:
BEGIN WORK;
UPDATE inventory SET quantity = quantity - 3 WHERE item = ’pants’;
COMMIT;
Data definition
The second group of keywords is the Data Definition Language (DDL). DDL allows the user to define new tables and associated elements. Most commercial SQL databases have proprietary extensions in their DDL, which allow control over nonstandard features of the database system. The most basic items of DDL are the CREATE,ALTER,RENAME,TRUNCATE and DROP commands:
* CREATE causes an object (a table, for example) to be created within the database.
* DROP causes an existing object within the database to be deleted, usually irretrievably.
* TRUNCATE deletes all data from a table (non-standard, but common SQL command).
* ALTER command permits the user to modify an existing object in various ways -- for example, adding a column to an existing table.
Example:
CREATE TABLE my_table (
my_field1 INT,
my_field2 VARCHAR (50),
my_field3 DATE NOT NULL,
PRIMARY KEY (my_field1, my_field2)
);
Data control
The third group of SQL keywords is the Data Control Language (DCL). DCL handles the authorization aspects of data and permits the user to control who has access to see or manipulate data within the database. Its two main keywords are:
GRANT
Authorizes one or more users to perform an operation or a set of operations on an object.
REVOKE
Removes or restricts the capability of a user to perform an operation or a set of operations.
Example:
GRANT SELECT, UPDATE ON my_table TO some_user, another_user.
Other
* ANSI-standard SQL supports double dash, --, as a single line comment identifier (some extensions also support curly brackets or C-style /* comments */ for multi-line comments).
Example:
SELECT * FROM inventory -- Retrieve everything from inventory table
* Some SQL servers allow User Defined Functions
Criticisms of SQL
Technically, SQL is a declarative computer language for use with “SQL databases“. Theorists and some practitioners note that many of the original SQL features were inspired by, but in violation of, the relational model for database management and its tuple calculus realization. Recent extensions to SQL achieved relational completeness, but have worsened the violations, as documented in The Third Manifesto.
In addition, there are also some criticisms about the practical use of SQL:
* Implementations are inconsistent and, usually, incompatible between vendors. In particular date and time syntax, string concatenation, nulls, and comparison case sensitivity often vary from vendor to vendor.
* The language makes it too easy to do a Cartesian join (joining all possible combinations), which results in “run-away“ result sets when WHERE clauses are mistyped. Cartesian joins are so rarely used in practice that requiring an explicit CARTESIAN keyword may be warranted.
* It is also possible to misconstruct a WHERE on an update or delete, thereby affecting more rows in a table than desired.
* SQL—and the relational model as it is—offer no standard way for handling tree-structures, i.e. rows recursively referring other rows of the same table. Oracle offers a “CONNECT BY“ clause, Microsoft offers recursive joins via Common Table Expressions, other solutions are database functions which use recursion and return a row set, as possible in PostgreSQL with PL/PgSQL.
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Active Server Pages (ASP) is Microsoft’s server-side script engine for dynamically-generated web pages. It is marketed as an add-on to Internet Information Services (IIS). Programming ASP websites is made easier by various built-in objects. Each object corresponds to a group of frequently-used functionality useful for creating dynamic web pages. In ASP 2.0 there are six such built-in objects: Application, ASPError, Request, Response, Server, and Session. Session, for example, is a cookie-based session object that maintains variables from page to page.
Most ASP pages are written in VBScript, but any other Active Scripting engine can be selected instead by using the @Language directive or the 《script language=“language“ runat=“server“》 syntax. JScript (Microsoft’s implementation of ECMAScript) is the other language that is usually available. PerlScript (a derivative of Perl) and others are available as third-party installable Active Scripting engines.
InstantASP and ChiliASP are technologies that run ASP without Windows Operating System. There are large open source communities on the WWW, such as ASPNuke, which produce ASP scripts, components and applications to be used for free under certain license terms.
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Adobe Dreamweaver, or simply Dreamweaver, is a web development tool, originally created by Macromedia. Initial versions of the application served as simple WYSIWYG HTML editors but more recent versions have incorporated notable support for many other web technologies such as CSS, JavaScript, and various server-side scripting frameworks. The software is available for both the Mac and Windows platforms, but can also be run on Unix-like platforms through the use of emulation software such as Wine. Dreamweaver is currently owned by Adobe Systems who acquired Macromedia in 2005.
Contents
Features
As a WYSIWYG editor, Dreamweaver can hide the details of pages’ HTML code from the user, making it possible for non-coders to create web pages and sites. A professional criticism of this approach is that it produces HTML pages whose file size and amount of HTML code is much larger than they should be, which can cause web browsers to perform poorly. This can be particularly true because the application makes it very easy to create table-based layouts. In addition, some web site developers have criticized Dreamweaver in the past for producing code that often does not comply with W3C standards though this has improved considerably in recent versions. Dreamweaver 8.0 (the version prior to the recently released 9.0 within CS3) performed poorly on the Acid2 Test, developed by the Web Standards Project. However, Macromedia has increased the support for CSS and other ways to lay out a page without tables in later versions of the application, with the ability to convert tables to layers and vice versa.
Adobe Dreamweaver CS3
Adobe Dreamweaver CS3
Dreamweaver allows users to preview websites in many browsers, provided that they are installed on their computer. It also has some site management tools, such as the ability to find and replace lines of text or code by whatever parameters specified across the entire site, and a templatization feature for creating multiple pages with similar structures. The behaviors panel also enables use of basic JavaScript without any coding knowledge.
With the advent of version MX, Macromedia incorporated dynamic content creation tools into Dreamweaver. In the spirit of HTML WYSIWYG tools, it allows users to connect to databases (such as MySQL and Microsoft Access) to filter and display content using scripting technologies such as Active Server Pages (ASP), ASP.NET, ColdFusion, JavaServer Pages (JSP), PHP, and more without any previous programming experience. Dreamweaver 8.0 also included support for WYSIWYG XSLT editing. Alternative solutions for web database application development are Alpha Five and FileMaker.
Dreamweaver can use “Extensions“ - small programs, which any web developer can write (usually in HTML and JavaScript). Extensions provide added functionality to the software for whoever wants to download and install them. Dreamweaver is supported by a large community of extension developers who make extensions available (both commercial and free) for most web development tasks from simple rollover effects to full-featured shopping carts.
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急用啊！！！！！！elias’ story的全文！！！！！

Elias’s story
1.My name is Elias. I am a poor black worker in South Africa. The time when I first met Nelson Mandela was a very difficult period of my life . I was twelve years old . It was in 1952 and Mandela was the black lawyer to whom I went for advice . He offered guidance to poor black people on their legal problems. He was generous with his time ,for which I was grateful.
I needed his help because I had very little education. I began school at six . The school where I studied for only two years was three kilomertes away . I had to leave because my family could not continue to pay the school fees and the bus fare . I could not read or write well . After trying hard ,I got a job in a gold mine ,However,this was a time when one had got to have a passbook to live in Johannesburg. Sadly I did not have it because I was not born there , and I worried about whether I would become out of work.
2.The day when Nelson Mandela helped me was one of my happiest . He told me how to get the correct papers so I could stay in Johannesburg. I became more hopeful about my future. I never forgot how kind Mandela was . When he organized the ANC Youth League, I joined it as soon as I could.He said:
“The last thirty years have seen the greatest numeber of laws stopping our rights and progress ,untill today we have reached a stage where we have almost no rights at all .”
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statement, 是什么意思

statement
n.声明;（思想、观点、文章主题等的）表现;（文字）陈述;结算单;
vi.（英国）对儿童进行特殊教育评估认定;
vt.申请（小孩）有特殊教育需要;
第三人称单数：statements过去分词：statemented复数：statements现在进行时：statementing过去式：statemented
例句
1.Here’sthatstatementinfull:
以下是这份声明的完整内容：
2.Ismythesisstatementconciseandclear?
我的论点陈述是否够简介和清晰？
3.Thisstatementisonlyhalfright.
这种说法只说对了一半。
4.Theincludestatementgivesphpprogrammersapowerfultooltoorganizetheirprojects.
include语句给了php程序员一个强大的项目管理工具。
5.Whatyouwearisastatementofwhoyouare.
穿什么样的衣服说明你是什么样的人。
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