MySQLSyntaxErrorException : Table XYZ doesn't exist

我正在使用JPA和c3p0，并尝试查询表并返回堆栈跟踪，声称该表不存在。我可以在例如DbVisualizer中打开与数据库的连接，然后查看其中的表。实际上，我的应用程序中的调试语句表明它能够建立连接并测试其可行性。但是，这并没有找到表格。

15:45:53.940 [http-8080-1] DEBUG o.h.e.j.i.LogicalConnectionImpl - Obtaining JDBC connection
15:45:53.940 [http-8080-1] DEBUG c.m.v.c.i.C3P0PooledConnectionPool - Testing PooledConnection [com.mchange.v2.c3p0.impl.NewPooledConnection@4d687dcd] on CHECKOUT.
15:45:53.949 [http-8080-1] DEBUG c.m.v.c.i.C3P0PooledConnectionPool - Test of PooledConnection [com.mchange.v2.c3p0.impl.NewPooledConnection@4d687dcd] on CHECKOUT has SUCCEEDED.
15:45:53.950 [http-8080-1] DEBUG c.m.v.resourcepool.BasicResourcePool - trace com.mchange.v2.resourcepool.BasicResourcePool@7930ebb [managed: 3, unused: 2, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@3e30e173)
15:45:53.950 [http-8080-1] DEBUG o.h.e.j.i.LogicalConnectionImpl - Obtained JDBC connection
15:45:53.966 [http-8080-1] DEBUG org.hibernate.SQL - select alert0_.rrdb_key as rrdb1_0_, alert0_.date as date0_, alert0_.hostname as hostname0_, alert0_.message as message0_, alert0_.program as program0_ from reportsDb.alerts alert0_ where (alert0_.message not like '%Anomolous%') and (alert0_.message not like '%Requeue%')
Hibernate: select alert0_.rrdb_key as rrdb1_0_, alert0_.date as date0_, alert0_.hostname as hostname0_, alert0_.message as message0_, alert0_.program as program0_ from reportsDb.alerts alert0_ where (alert0_.message not like '%Anomolous%') and (alert0_.message not like '%Requeue%')
15:45:54.013 [http-8080-1] DEBUG c.m.v2.c3p0.impl.NewPooledConnection - com.mchange.v2.c3p0.impl.NewPooledConnection@4d687dcd handling a throwable.
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'reportsDb.alerts' doesn't exist
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.6.0_45]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) ~[na:1.6.0_45]
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) ~[na:1.6.0_45]
    at java.lang.reflect.Constructor.newInstance(Constructor.java:513) ~[na:1.6.0_45]
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) ~[mysql-connector-java-5.1.6.jar:na]
...

这是persistence.xml(在/src/main/resources/META-INF中):

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
    <persistence-unit name="reportsDb" transaction-type="RESOURCE_LOCAL">
        <description>Hibernate</description>
        <class>com.pronto.mexp.common.entity.Alert</class>
    </persistence-unit>
</persistence>

applicationContext.xml的一个小节:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context-3.1.xsd">

    <bean id="jpaDialect" class="org.springframework.orm.jpa.vendor.HibernateJpaDialect"/>

    <bean id="reportsDbEntityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="dataSource" ref="reportsDbDataSource" />
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
                <property name="showSql" value="true"/>
                <property name="generateDdl" value="false" />
                <property name="databasePlatform" value="org.hibernate.dialect.MySQL5InnoDBDialect" />
            </bean>
        </property>
        <property name="persistenceUnitName" value="reportsDb" />
        <property name="jpaDialect" ref="jpaDialect"/>
    </bean>

    <bean id="reportsDbDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
        <property name="driverClass" value="com.mysql.jdbc.Driver"/>
        <!--<property name="jdbcUrl" value="jdbc:mysql://devdbrw01:3306/mexp"/>-->
        <property name="jdbcUrl" value="jdbc:mysql://report101:3306/worker_events"/>
        <property name="user" value="********"/>
        <property name="password" value="********"/>
        <property name="acquireRetryDelay" value="1000"/>
        <property name="acquireRetryAttempts" value="4"/>
        <property name="breakAfterAcquireFailure" value="false"/>
        <property name="testConnectionOnCheckout" value="true"/>
        <property name="maxConnectionAge" value="14400"/>
        <property name="maxIdleTimeExcessConnections" value="1800"/>
    </bean>

    <!-- DAOs -->
    <bean id="genericReportsDbDAO" class="com.pronto.mexp.common.dal.GenericReportsDbJPADAOImpl"/>

    <bean id="alertJPADAO" class="com.pronto.mexp.dal.AlertJPADAOImpl" parent="genericReportsDbDAO"/>
</beans>

我发现可疑的是 hibernate 查询的一部分，它尝试查询select ... from reportsDb.alerts alert0_-如何确认“reportsDb”实际上代表我在applicationContext.xml中指定的数据源？

预计到达时间:
实体Alert如下所示:

@Entity
@Table(name = "alerts", catalog = "reportsDb")
public class Alert {

    int rrdbKey;
    String hostname = "";
    String message = "";
    String program = "";
    Date date = new Date();

    @javax.persistence.Column(name = "rrdb_key", nullable = false, insertable = false, updatable = false, length = 10, precision = 0)
    @Id
    public int getRrdbKey() {
        return rrdbKey;
    }

    public void setRrdbKey(int rrdbKey) {
        this.rrdbKey = rrdbKey;
    }

    @javax.persistence.Column(name = "hostname", nullable = false, insertable = false, updatable = false, length = 32, precision = 0)
    @Basic
    public String getHostname() {
        return hostname;
    }

    public void setHostname(String hostname) {
        this.hostname = hostname;
    }

    @javax.persistence.Column(name = "message", nullable = false, insertable = false, updatable = false, length = 128, precision = 0)
    @Basic
    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    @javax.persistence.Column(name = "program", nullable = true, insertable = false, updatable = false, length = 40, precision = 0)
    @Basic
    public String getProgram() {
        return program;
    }

    public void setProgram(String program) {
        this.program = program;
    }

    @javax.persistence.Column(name = "date", nullable = false, insertable = false, updatable = false, length = 19, precision = 0)
    @Basic
    public Date getDate() {
        return date;
    }

    public void setDate(Date date) {
        this.date = date;
    }
}

最佳答案

从您的实体定义中，删除catalog = 'reportsDb'部分，因为它已用于构建查询，例如select from 'reportsDb.alerts'。
Mysql不使用目录AFAIK。

关于MySQLSyntaxErrorException : Table XYZ doesn't exist，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/16287821/