MySQL用文本方式将数据装入一个数据库表
如果一条一条地输入,很麻烦。我们可以用文本文件的方式将所有记录加入你的数据库表中。创建一个文本文件ldquo;mysql.txtrdquo
如果一条一条地输入,很麻烦。我们可以用文本文件的方式将所有记录加入你的数据库表中。创建一个文本文件“mysql.txt”,每行包含一个记录,用定位符(tab)把值分开,并且以在CREATE TABLE语句中列出的列次序给出,例如:
使用下面命令将文本文件“mytable.txt”装载到mytable表中:mysql> LOAD DATA LOCAL INFILE "mytable.txt" INTO TABLE tablename;
跟目录:wamp/
select *from information_schema.tables
where table_name = 'TableName'
Mysql使用Describe命令判断字段是否存在
工作时需要取得MySQL中一个表的字段是否存在 于是就使用Describe命令来判断 mysql_connect('localhost', 'root', 'root'); mysql_select_db('demo'); $test = mysql_query('Describe cdb_posts first'); $test = mysql_fetch_array($test); $test[0]返回的是该字段的名
工作时需要取得MySQL中一个表的字段是否存在
于是就使用Describe命令来判断
mysql_connect('localhost', 'root', 'root');
mysql_select_db('demo');
$test = mysql_query('Describe cdb_posts first');
$test = mysql_fetch_array($test);
$test[0]返回的是该字段的名称,比如我要查询first字段,返回的就是first
如果此字段不存在返回的就是NULL,通过这样可以判断一个字段是否存在
附加资料:
describe命令
一、describe命令用于查看特定表的详细设计信息,例如为了查看guestbook表的设计信息,可用:
describe guestbook
二、可通过”show comnus”来查看数据库中表的列名,有两种使用方式:
show columns form 表名 from 数据库名
或者:
show columns from 数据库名.表名
三、用describe命令查询具体列的信息
describe guestbook id
就是查询guestbook中id字段的列信息
{DESCRIBE | DESC} tbl_name [col_name | wild]
DESCRIBE 是 SHOW COLUMNS FROM 的缩写。DESCRIBE 提供有关一个表的列信息。col_name 可以是一个列名或是一个包含 SQL 通配符字符 “%” 和 “_” 的字符串。没有必要用引号包围字符串。
如果列类型不同于你所期望的基于一个 CREATE TABLE 语句建立的列,,注意 MySQL 有时会更改列类型。这个语句是提供给与 Oracle 兼容的。

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