前面兩天介紹的query語法基本上跟SQL語法沒有多大的關聯性，屬於比較直觀的寫法，如果要比較複雜的query的話，因為GORM底層是Hibernate，故當然可以用HQL語法(SQL like)的語法來做查詢，今天又是一周的上班第一天，沒有太多時間鑽研太深入的HQL語法，故簡單介紹HQL語法以及用Integration Test來測試HQL語法是否正確，對HQL有興趣的話可以參考
，以及下載Grails官方API來看，裡面也有一些範例
HQL語法基本上還是從Domain Class出發，主要有四種方法:find(), findAll(), executeQuery以及executeUpdate，基本語法如下今天將以findAll為例。

(Domain class name).方法(HQL語法)

以User及Post Domain class為主，兩者是一對多關係，忘記提如果在多的那一方Domain Class中加入belongsTo=[xxx(variable):XXX(Domain Class)]，Grails將自動產生新方法addTo*/removeFrom，

(Domain Class Name).addTo*

(Domain Class Name).removeFrom*

以此case為例，則是User.addToPosts(new Post(.....))

使用Integration Test簡單範例code如下:

class PostIntegrationSpec extends IntegrationSpec {

	def setup() {
	}

	def cleanup() {
	}

	void "Test Adding post function"() {
		
		given:'HQL Syntax Test'
		def Jason=new User(userId:'Jason', password:'i74960X',
			profile: new Profile(fullName:'JasonGoo', email:'yiren.goo@gmail.com'),
			personalPage:'https://www.facebook.com/NeverFigureOut').save(failOnError:true)

		def John=new User(userId:'John', password:'JohnWu',
		profile: new Profile(fullName:'John Wu', email:'John.wu@gmail.com'),
		personalPage:'https://john.blogger.com').save(failOnError:true)
		
		Jason.addToPosts(new Post(content:'Just finish a horrible day...'))
		Jason.addToPosts(new Post(content:'What can I do to have more time?'))
		Jason.addToPosts(new Post(content:'What a sunny day'))
		
		John.addToPosts(new Post(content:'Today is not my day'))
		John.addToPosts(new Post(content:'What a horrible Monday!!!'))
	
		when:'Executing findAll function'
		
		def totalPosts=Post.findAll ("from Post").size()
			//findAll回傳是list
		def postNumberForJason=Post.findAll("from Post p "+
			"where p.user.userId=:name",[name:'Jason']).size()
			//使用:namej作為query變數可以避免SQL injection
		
		then: 'Check if how many posts are linked to the user'
		5 == totalPosts
		3 == postNumberForJason
	}
}

Integration Test結果:

| Loading Grails 2.2.3
| Configuring classpath.
| Environment set to test.....
| Packaging Grails application.....
| Packaging Grails application.....
| Compiling 1 source files...
| Running 1 spock test... 1 of 1
| Completed 1 spock test, 0 failed in 544ms
| Tests PASSED - view reports in D:\groovy\JasonMicroBlog\target\test-reports

明天將開始介紹controller的部分...