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在Java中获取数据库元数据的最简单方法?

ddlutils metadata database java

Andrew Swan · 技术社区 · 17 年前

我熟悉 java.sql.DatabaseMetaData 接口,但我发现它使用起来相当笨拙。例如,为了找出表名,必须调用 getTables 然后循环返回 ResultSet ,使用已知的文本作为列名称。

有没有更简单的方法来获取数据库元数据?

2 回复 | 直到 9 年前

Andrew Swan 17 年前

很容易用 DdlUtils :

import javax.sql.DataSource;
import org.apache.ddlutils.Platform;
import org.apache.ddlutils.PlatformFactory;
import org.apache.ddlutils.model.Database;
import org.apache.ddlutils.platform.hsqldb.HsqlDbPlatform;

public void readMetaData(final DataSource dataSource) {
  final Platform platform = PlatformFactory.createNewPlatformInstance(dataSource);
  final Database database = platform.readModelFromDatabase("someName");
  // Inspect the database as required; has objects like Table/Column/etc.
}

Sualeh Fatehi 14 年前

看看SchemaCrawler(免费和开源),它是另一个为此目的而设计的API。一些SchemaCrawler示例代码:

    // Create the options
final SchemaCrawlerOptions options = new SchemaCrawlerOptions();
// Set what details are required in the schema - this affects the
// time taken to crawl the schema
options.setSchemaInfoLevel(SchemaInfoLevel.standard());
options.setShowStoredProcedures(false);
// Sorting options
options.setAlphabeticalSortForTableColumns(true);

// Get the schema definition 
// (the database connection is managed outside of this code snippet)
final Database database = SchemaCrawlerUtility.getDatabase(connection, options);

for (final Catalog catalog: database.getCatalogs())
{
  for (final Schema schema: catalog.getSchemas())
  {
    System.out.println(schema);
    for (final Table table: schema.getTables())
    {
      System.out.print("o--> " + table);
      if (table instanceof View)
      {
        System.out.println(" (VIEW)");
      }
      else
      {
        System.out.println();
      }

      for (final Column column: table.getColumns())
      {
        System.out.println("     o--> " + column + " (" + column.getType()
                           + ")");
      }
    }
  }
}

http://schemacrawler.sourceforge.net/