mysql - Play Framework 连接数据库

Question

我一直在关注 Play Framework 的 Typesafe 在线培训(我在网页设计方面是一个完全的初学者)，一切正常，直到我们应该连接到数据库的部分。

当我看到本网站第二课的第二个视频时: https://typesafe.com/how/online-training/play-java

我遇到了一个问题，这是我尝试刷新浏览器时收到的错误消息:

Cannot connect to database [default]
In /Users/Arash/playconf/conf/application.conf at line 43.
40 db.default.driver=com.mysql.jdbc.Driver
41
 # Here we add the database that we have created locally
43 db.default.url="jdbc:mysql://localhost:3306/playconf"
44
45 # We set this to root, we login as root with no password
46 db.default.user=root

这是我终端中的错误信息(运行 Play )

[error] c.j.b.h.AbstractConnectionHook - Failed to obtain initial connection Sleeping for 0ms and trying again. Attempts left: 0. Exception: null.Message:Unknown database 'playconf' [error] application -

! @6hmk31f56 - Internal server error, for (GET) [/] ->

play.api.Configuration$$anon$1: Configuration error[Cannot connect to database [default]] at play.api.Configuration$.play$api$Configuration$$configError(Configuration.scala:92) ~[play_2.10.jar:2.2.2] at play.api.Configuration.reportError(Configuration.scala:570) ~[play_2.10.jar:2.2.2] at play.api.db.BoneCPPlugin$$anonfun$onStart$1.apply(DB.scala:252) ~[play-jdbc_2.10.jar:2.2.2] at play.api.db.BoneCPPlugin$$anonfun$onStart$1.apply(DB.scala:243) ~[play-jdbc_2.10.jar:2.2.2] at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244) ~[scala-library.jar:na] at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244) ~[scala-library.jar:na] Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown database 'playconf' at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0] at java.lang.reflect.Constructor.newInstance(Constructor.java:408) ~[na:1.8.0] at com.mysql.jdbc.Util.handleNewInstance(Util.java:411) ~[mysql-connector-java-5.1.26.jar:na] at com.mysql.jdbc.Util.getInstance(Util.java:386) ~[mysql-connector-java-5.1.26.jar:na]

我已尽可能准确地遵循所有内容，但出现此错误，我整天都被困在这里。很郁闷...

然后我想，哦，也许我没有mysql？于是我用homebrew安装了mysql，再次尝试，还是报了同样的错误。

这是我与数据库有关的代码:

在配置文件中:

# We add our sql driver, which we have added in the build.sbt file
 # db.default.driver=org.h2.Driver # This is the original, commented out originally
 db.default.driver=com.mysql.jdbc.Driver

 # Here we add the database that we have created locally
 db.default.url="jdbc:mysql://localhost:3306/playconf"

 # We set this to root, we login as root with no password
 db.default.user=root

在构建文件中:

libraryDependencies ++= Seq(
    javaEbean,
    "mysql" % "mysql-connector-java" % "5.1.26",
    "org.webjars" %% "webjars-play" % "2.2.0",
    "org.webjars" % "bootstrap" % "2.3.1")

好的，看来我必须创建数据库，现在我已经创建了，但是我无法访问数据库。我收到错误 1044 (42000):用户 ''@'localhost' 对数据库 'playconf' 的访问被拒绝

Answer 1

您需要在您的 MySQL 服务器中手动创建此 playconf 数据库，例如使用常见的 DB GUI(它不会像 H2 那样自动创建)

执行此操作后，终止正在运行的应用程序并再次运行它。