首页 > 解决方案 > 当 useInformationSchema 为真时,DatabaseMetadata.getImportedKeys() 在 where 子句中抛出列 'REFERENCED_TABLE_NAME' 不明确

问题描述

我正在尝试使用DatabaseMetaData检索 MySQL 数据库上的表的键,并尝试使用 InformationSchema 来执行此操作。MySQL 配置属性

import java.sql.*

class DataLoader {

    static final String JDBC_DRIVER = "com.mysql.jdbc.Driver"
    static final String DB_URL = "jdbc:mysql://localhost:3306/mydb?useInformationSchema=true"
    static final String USER = "user"
    static final String PASS = "password"
    static final String DB = "mydb"

    public static void main(String[] args) {
        Connection conn = null
        Statement stmt = null
        try {
            Class.forName(JDBC_DRIVER)
            conn = DriverManager.getConnection(DB_URL, USER, PASS)

            println "Database Product Name: " + conn.getMetaData().getDatabaseProductName()
            println "Database Product Version: " + conn.getMetaData().getDatabaseProductVersion()
            println "JDBC Driver: " + conn.getMetaData().getDriverName()
            println "Driver Version: " + conn.getMetaData().getDriverVersion()

            ResultSet importedKeysRS = conn.getMetaData().getImportedKeys(DB, null, "user")

        } catch (Exception e) {
            e.printStackTrace()
        } finally {
            try {
                if (stmt != null) {
                    stmt.close()
                    conn.close()
                }
            } catch (SQLException se) {
            }// do nothing
            try {
                if (conn != null)
                    conn.close()
            } catch (SQLException se) {
                se.printStackTrace()
            }
        }
    }
}

当我执行上面的 groovy 代码时,以下是抛出的异常。

Database Product Name: MySQL
Database Product Version: 5.6.15-rel63.0-log
JDBC Driver: MySQL-AB JDBC Driver
Driver Version: mysql-connector-java-5.1.6 ( Revision: ${svn.Revision} )
com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Column 'REFERENCED_TABLE_NAME' in where clause is ambiguous
    at com.mysql.jdbc.DatabaseMetaDataUsingInfoSchema.executeMetadataQuery(DatabaseMetaDataUsingInfoSchema.java:50)
    at com.mysql.jdbc.DatabaseMetaDataUsingInfoSchema.getImportedKeys(DatabaseMetaDataUsingInfoSchema.java:780)

当我useInformationSchema=true从 JDBC URL 中删除属性时,它可以正常工作,但执行时间太长getImportedKeys()

我该如何启用useInformationSchema

如果我不能使用 property useInformationSchema,我该怎么做才能使查询getImportedKeys()getExportedKeys()运行得更快?

标签: mysqldatabasejdbcdatabase-metadata

解决方案


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