Question

嘿，我是一个绝对的红宝石，希望你能帮助我。我想用不同的部门（部门A，B，C ......）进行很多SQL查询。

我想将部门保存到数组并迭代它，使用循环等等。

这是我的旧代码：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD//EN"
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
        <hibernate-configuration>
        <session-factory>
        <property name="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</property>
        <property name="hibernate.connection.drive_class">oracle.jdbc.OracleDriver</property>
        <property name="hibernate.connection.url">jdbc:oracle:thin:@localhost:1521:xe</property>
        <property name="hibernate.connection.username">SYSTEM</property>
        <property name="hibernate.connection.password">****</property>
        <property name="show_sql">true</property>
        <mapping class="Entity.Address"/>
        <mapping class="Entity.Student"/>

    </session-factory>

这是我的伪代码：

#!/usr/bin/ruby
require 'mysql2'
##Connect to my Database
db = Mysql2::Client.new(:host => "localhost", :username => "MyUserName", :password => "MyPassword", :port => 3306, :database => "MyTest-Database" )

#Mysql querys
sql_A= "SELECT RMKPI FROM `Table1` WHERE `Department` = 'A' "
sql_B= "SELECT RMKPI FROM `Table1` WHERE `Department` = 'B' "

#Execute the querys
results_PO = db.query(sql_A)
results_DevMuM = db.query(sql_A)

我该怎么做？非常感谢

Answer 1

DEPARTMENTS = %w|A B C|
results = DEPARTMENTS.map do |department|
  query = "SELECT RMKPI FROM `Table1` WHERE `Department` = '#{department}'"
  [department, db.query(query)]
end.to_h

现在你有一个{ departments ⇒ results }的哈希值。要访问给定部门的结果，请使用：

results['A']

Sidenote ：我建议你google ActiveRecord或任何其他ROM来简化并使数据库查询工作更安全。

迭代数组并在ruby中使用变量

1 个答案: