请帮翻译以下英文,谢谢,急用?(50分)

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bluesea07

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Columns and Datatypes
Tables are made up of columns. A column contains a particular piece of information within a table.
Column A single field in a table. All tables are made up of one or more columns.
The best way to understand this is to envision database tables as grids, somewhat like spreadsheets. Each column in the grid contains a particular piece of information. In a customer table, for example, one column contains the customer number, another contains the customer name, and the address, city, state, and zip are all stored in their own columns.
Breaking Up Data It is extremely important to break data into multiple columns correctly. For example, city, state, and zip should always be separate columns. By breaking these out, it becomes possible to sort or filter data by specific columns (for example, to find all customers in a particular state or in a particular city). If city and state are combined into one column, it would be extremely difficult to sort or filter by state.
Each column in a database has an associated datatype. A datatype defines what type of data the column can contain. For example, if the column is to contain a number (perhaps the number of items in an order), the datatype would be a numeric datatype. If the column were to contain dates, text, notes, currency amounts, and so on, the appropriate datatype would be used to specify this.
Datatype A type of allowed data. Every table column has an associated datatype that restricts (or allows) specific data in that column.
Datatypes restrict the type of data that can be stored in a column (for example, preventing the entry of alphabetical characters into a numeric field). Datatypes also help sort data correctly, and play an important role in optimizing disk usage. As such, special attention must be given to picking the right datatype when tables are created.
Datatype Compatibility Datatypes and their names are one of the primary sources of SQL incompatibility. While most basic datatypes are supported consistently, many more advanced datatypes are not. And worse, occasionally you'll find that the same datatype is referred to by different names in different DBMSs. There is not much you cando
about this, but it is important to keep in mind when you create table schemas.
Rows
Data in a table is stored in rows;
each record saved is stored in its own row. Again, envisioning a table as a spreadsheet style grid, the vertical columns in the grid are the table columns, and the horizontal rows are the table rows.
For example, a customers table might store one customer per row. The number of rows in the table is the number of records in it.
Row A record in a table.
Records or Rows? You may hear users refer to database records when referring to rows. For the most part, the two terms are used interchangeably, but row is technically the correct term.
 
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xmh_31

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Columns and Datatypes
列和数据类型
Tables are made up of columns. A column contains a particular piece of information within a table.
表由列组成. 列包含表内的详细信息片段.
Column A single field in a table. All tables are made up of one or more columns.
列A 表中的单一字段. 所有的表由一个或者更多的列组成.
The best way to understand this is to envision database tables as grids, somewhat like spreadsheets. Each column in the grid contains a particular piece of information. In a customer table, for example, one column contains the customer number, another contains the customer name, and the address, city, state, and zip are all stored in their own columns.
理解表的最好方法是把表想象成表格, 有点象电子表格, 表格的每一列包含特殊信息. 例如, 在一个客户表中,一列包含客户编码,另外的列包含客户名称,地址,城市,州,邮编,这些都存储在表列里
Breaking Up Data It is extremely important to break data into multiple columns correctly. For example, city, state, and zip should always be separate columns. By breaking these out, it becomes possible to sort or filter data by specific columns (for example, to find all customers in a particular state or in a particular city). If city and state are combined into one column, it would be extremely difficult to sort or filter by state.
分离数据 把数据正确的分离到多个表列里极其重要,例如,城市,州,邮编总是应该占有独立的列。通过分离,才能对指定的列(例如,查找指定周或城市的所有客户)进行排序或过滤。如果城市和州组合成一个列,那么按州排序或过滤将会极其困难。
Each column in a database has an associated datatype. A datatype defines what type of data the column can contain. For example, if the column is to contain a number (perhaps the number of items in an order), the datatype would be a numeric datatype. If the column were to contain dates, text, notes, currency amounts, and so on, the appropriate datatype would be used to specify this.
数据库的每一列都有关联的数据类型。数据类型定义了该列能包换什么类型的数据。例如,如果列包含一个数字(或许是订单的项编号),数据类型将是numeric类型。如果列包含日期,文本,注释,货币,数量等,那么相应的列应指定适当的类型。
Datatype A type of allowed data. Every table column has an associated datatype that restricts (or allows) specific data in that column.
数据类型A允许的数据类型。每个表列有合适的数据类型来约束该列所允许的数据。
Datatypes restrict the type of data that can be stored in a column (for example, preventing the entry of alphabetical characters into a numeric field). Datatypes also help sort data correctly, and play an important role in optimizing disk usage. As such, special attention must be given to picking the right datatype when tables are created.
数据类型(Datatypes)约束能够存储在列中数据的类型(例如,不能把字符数据存入数字字段中)数据类型也帮助正确的排序数据,并且在优化存储数据时扮演重要角色。同样,在创建表时需要特别注意的是选取正确的数据类型。
Datatype Compatibility Datatypes and their names are one of the primary sources of SQL incompatibility. While most basic datatypes are supported consistently, many more advanced datatypes are not. And worse, occasionally you'll find that the same datatype is referred to by different names in different DBMSs. There is not much you cando
about this, but it is important to keep in mind when you create table schemas.
数据类型兼容性 数据类型及名称不兼容主要源于SQL不兼容。大多数基本的数据类型被一贯的支持,更多的高级数据类型却不是这样。更糟糕的是,偶尔地你会发现同样的数据类型在不同的DBMS中会指定不同的名字。你没办法改变这一点,但是在创建表结构时一定要注意。
Rows

Data in a table is stored in rows;
each record saved is stored in its own row. Again, envisioning a table as a spreadsheet style grid, the vertical columns in the grid are the table columns, and the horizontal rows are the table rows.
表中的数据存储在行中;每条记录存储在自己的行中,再次把表想象成电子表格中的表格,表格的垂直列示表的列,横行就是表的行。
For example, a customers table might store one customer per row. The number of rows in the table is the number of records in it.
例如,客户表可以每行存储一个客户,表的行号是记录号。
Row A record in a table.
行A 表中的记录。
Records or Rows? You may hear users refer to database records when referring to rows. For the most part, the two terms are used interchangeably, but row is technically the correct term.
记录还是行?你可能在谈到行的时候听到用户说数据库记录。大多数情况下,这两个术语交替使用,但是行是专业的更恰当术语。
 
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