it can give operator the ability to view and modify the data all at once (一次性的) by granting access permission on schemas.
we can control user operations by granting access permission on schemas.
make managing user permission easier.
we can create whatever schema you want.
data is organized underneath a collection of items called schemas.
trustworthy —untrustworthy
protect against 防范，预防
to efficient store data within a mimum of redundancy 最低冗余 while protecting against inconsistencies
for instance
simultaneously prevent them from accessing anything that’s in the warehouse schema by denying permissions over there
deny permissions 拒绝授权
the system will deny permissions to users who do not meet the security requirements.
in our current databases
separation of resources is a convern 资源的分离是个需要关注的问题
think through 仔细考虑，全面思考下
think through your schema organization 仔细考虑下你的模式架构
implement it early on in the the design process
I’m going to go head and collapse the tab that’s open on the screen
solar panel equipment 太阳板
I was working on my computer when suddenly the screen is frozen and I can’t do anything.
The screen is fronzen is frozen on this page and won’t load the next one.
in order to grant access permissions
we haven’t set up any additional user accounts yet.
syntax 语法
it’s pretty simple
we’re automatically assigning ownership of the schema to ourselves.
it’s always a good idea to review the SQL syntax
so that you can start to get familiar with the exact commands that the server is running
The PgAdmin interface that we’re using gives users a lot of assistance in creating these commands through the options in the dialog window like this one.
As you gain experience working with postgres databases ,it’ll be much easier to simply type these kinds of commands in on your own.
you’ll see it over here in the browser window
move down to
head up to the tools menu
That’ll open up a new tab in the interface
pop-up window
drop-down box
issure command 发出指令
we can start issuing comands directly to the server
type out the code 打出代码来
human resources with an underscore between the two words。
下划线 underscore
use underscores to separate words in the file name .
在xxx下面划线，强调
the report underscores the importance of education
it’s a general practice to use all capital letters 使用全大写字母是一种常见做法
the PgAdmin interface also recognizes keywords.
color the words in a purple font 用紫色字体给文字上色 to make the code easier to read
all of your commands should end with a semicolon. 分号
after typing this out，press the play button on the toolbar 工具栏 to execute the command
you can press the f5 shortcut key on your keyboard
shortcut key 快捷键
sending commands like this way doesn’t always cause changes to appear 并不会导致变化出现
our database has a couple of schemas 几个。。
If your query window is still open from the previous movie ,you can go head and close it using
the X in the upper right-hand corner of the screen.如果屏幕之前开发了，现在依旧开着，那么可以用右上角的X 去关闭它
you can use this dropdown menu to choose a different schema
both actions will have the exact same result 两个操作结果都一样
allow you split the table across multiple pysical files on your hard drive 在你的硬盘上
This can be useful for data tables that are expected to become very large 预计会变得很大
By placing portions of the data on different hard drives，you can increase read and write performance of the database.
this is where we’ll set up the column definition that’ll make up the table’s structure
Click on the plus button on the right-hand side to add in your first row.
