ActiveRecord create table

 

cat app.rb<br />
require &#39;active_record&#39;

ActiveRecord::Base.establish_connection(adapter: 'postgresql', database: 'datasetter_development')
#连接本地的数据库
class User &lt; ActiveRecord::Base<br />
end
#再次运行创建table数据的时候，必须存在该表数据的class，进行migrate的时候可以不必存在。
class Account &lt; ActiveRecord::Base<br />
end
class CreateAccountTable &lt; ActiveRecord::Migration[5.2]<br />
&nbsp; def change<br />
&nbsp;&nbsp;&nbsp; create_table :accounts do |table|<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; table.string :first_name<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; table.integer :last_name<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; table.timestamps null: false<br />
&nbsp;&nbsp;&nbsp; end<br />
&nbsp; end<br />
end
# Create the table 
#运行一次ruby app.rb 就会进行migrate，再次运行脚本的时候，就需要把创建table的语句注释掉，不然会报错，提示该表已经存在了<br />
#CreateAccountTable.migrate(:up)
# Drop the table<br />
#CreateAccountTable migrate(:down)
<p>#创建数据，十万条数据</p>
(1..10000).each do |i|<br />
&nbsp; Account.create first_name: &quot;jim&quot;, last_name: &quot;#{(&#39;A&#39;..&#39;Z&#39;).to_a.shuffle[0,5].join}&quot;<br />
&nbsp; puts Account.all.size<br />
end
(1..10000).each do |i|<br />
&nbsp; Account.create last_name: &quot;jim&quot;, first_name: &quot;#{(&#39;A&#39;..&#39;Z&#39;).to_a.shuffle[0,5].join}&quot;<br />
&nbsp; puts Account.all.size<br />
end
(1..80000).each do |i|<br />
&nbsp; Account.create first_name: &quot;#{(&#39;A&#39;..&#39;Z&#39;).to_a.shuffle[0,5].join}&quot;, last_name: &quot;#{(&#39;A&#39;..&#39;Z&#39;).to_a.shuffle[0,5].join}&quot;<br />
&nbsp; puts Account.all.size<br />
end

 </p>