如何通过 JDBC 将数据流式传输到 MariaDB

I want to store BLOB data into MariaDB using MariaDB connector and I try to find the most efficient solution. Now I'm using setBlob() or setBinaryStream() method to store data. But it is so slow comparing to direct streaming of data to database. I used streaming for Oracle database and everything worked fast and perfectly. But since I changed the database to MariaDB, direct streaming doesn't work.

直接流的代码如下:

        Blob localBlob =  lrs.getBlob("MyData");

        try {
            los = localBlob.setBinaryStream(1);
        } catch (Throwable t) {
        }
        int countBytesRead;
        // md5 hash
        InputStream dis = new DigestInputStream(inputStreamArgument, localHash);
        byte[] localBuffer = new byte[BUFFER_SIZE];
        while ((countBytesRead = dis.read(localBuffer)) >= 0) {
            los.write(localBuffer, 0, countBytesRead);
        }
        los.close();
        inputStreamArgument.close();
        lstmt.close();

推荐答案

简答 - 从今天起您无法流式传输 blob.此连接器始终将至少一整行读入内存.此外，MariaDB 服务器(以及 MySQL)不能非常有效地处理 blob，它还会将整个博客加载到内存中，仅在服务器端.如果您想要自己动手流式传输，也许您可​​以将 blob 拆分为更小的块，例如 4K，并将它们存储在专用表中的不同行中.您可以 SELECT * from my_blob 将其读取为多行，并使用例如 setFetchSize(1) 一次读取一个块.