jetbrick-orm/src/main/java/jetbrick/dao/orm/DbHelper.java
public boolean tableExist(String name) {
        Connection conn = null;
        ResultSet rs = null;
        try {
            conn = getConnection();
            DatabaseMetaData metaData = conn.getMetaData();
            rs = metaData.getTables(null, null, name.toUpperCase(), new String[] { "TABLE" });
            return rs.next();
        } catch (SQLException e) {
            throw new DbException(e);
        } finally {
            DbUtils.closeQuietly(rs);
            closeConnection(conn);
        }
    }
public boolean tableExist(String name) {
        Connection conn = null;
        ResultSet rs = null;
        try {
            conn = getConnection();
            DatabaseMetaData metaData = conn.getMetaData();
            rs = metaData.getTables(null, null, name.toUpperCase(), new String[] { "TABLE" });
            return rs.next();
        } catch (SQLException e) {
            throw new DbException(e);
        } finally {
            DbUtils.closeQuietly(rs);
            closeConnection(conn);
        }
    }
判断表是否已经存在