Question

我将两个数据库与liquibase java API 3.3.2进行了比较，然后生成了changelog.xml文件。现在，我想生成将更新目标数据库的sql脚本。这是我的代码：

Database database;
Database database2;
try {
    database = CommandLineUtils.createDatabaseObject(org.postgresql.Driver.class.getClassLoader(), "jdbc:postgresql://localhost:5432/loan", "postgres", "", "org.postgresql.Driver", null, null, false, false, null, null, null, null, null);
    database2=CommandLineUtils.createDatabaseObject(org.postgresql.Driver.class.getClassLoader(), "jdbc:postgresql://localhost:5432/loan2", "postgres", "", "org.postgresql.Driver", null, null, false, false, null, null, null, null, null);
    Liquibase liquibase = new Liquibase("", new FileSystemResourceAccessor(), database);
    DiffResult result = liquibase.diff(database, database2, new CompareControl());
    DiffToChangeLog diffLog = new DiffToChangeLog(result, new DiffOutputControl());
    diffLog.print(System.out);
    //new DiffToReport(result, System.out).print();

} catch (Exception e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

修改以下是我的表现，感谢Steve donie：

        Database database;
    Database database2;
    try {
        database = CommandLineUtils.createDatabaseObject(org.postgresql.Driver.class.getClassLoader(), "jdbc:postgresql://localhost:5432/loan", "postgres", "", "org.postgresql.Driver", null, null, false, false, null, null, null, null, null);
        database2= CommandLineUtils.createDatabaseObject(org.postgresql.Driver.class.getClassLoader(), "jdbc:postgresql://localhost:5432/loan2", "postgres", "", "org.postgresql.Driver", null, null, false, false, null, null, null, null, null);

        // generate the changelog that contains the differences
        CommandLineUtils.doDiffToChangeLog("changelog.xml", database, database2, new DiffOutputControl(), null, null);

        // generate the sql script from the changeLog (without executing it)
        File sql = new File("output.sql");
        Liquibase liquibase = new Liquibase("changelog.xml", new FileSystemResourceAccessor(), database);
        liquibase.update("Update", new FileWriter(sql));
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

Answer 1

解决这个问题的一种方法是从命令行运行时查看Liquibase本身的功能。在这种情况下，您通常会使用diffChangeLog命令创建更改日志，然后运行updateSQL以生成更新数据库所需的SQL。查看liquibase.integration.commandline.Main的Liquibase源代码，我看到what it does is to use the Liquibase.update() method带有指定a non-null output writer的参数（这是SQL将保存到的文件）。

liquibase - 如何在使用java比较两个数据库后从更改日志生成sql脚本？

1 个答案: