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What does it mean if binary data is “4 byte single format” and how do I read it in JavaScript?

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问题 I have to read a binary file which is said to be encoded 4 byte single format and never having to work with binary data, I don't know what this means. I can do this reading a file with binary data in JavaScript: d = new FileReader(); d.onload = function (e) { var i, len; // grab a "chunk" response_buffer = e.target.result.slice(0, 1024); view = new DataView(response_buffer); for (i = 0, len = response_buffer.byteLength; i < len; i += 1) { // hmhm console.log(view.getUint8(i)); } } d

PDO - Insert blob image into MySQL

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问题 I have some problems Notice: Array to string conversion in x\contact_ajouter_verif.php on line 17 This is my form : <form action="contact_ajouter_verif.php" method="post" name="ajoutContact" enctype="multipart/form-data" > <fieldset> <label>Nom :</label> <input size="30%" type="text" placeholder="" name="nom" /> <label>Numéro :</label> <input size="30%" type="number" placeholder="" name="num" /> <label>Image au format png :</label><input type="file" name="img" /> </fieldset> <input name=

Mysql基础——基本数据类型

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这篇文章主要介绍的是Mysql的基础入门知识——基本数据库类型。虽然对于数据库的知识学到了很多，但是却往往容易忽略数据库中最基本的基础知识。另外，数据库的基础类型对于数据库的优化也非常重要，所以本文在这里对数据库的基础类型做一下总结。 mysql支持多种类型，大致可以分为3类：数值、日期/时间和字符串（字符）类型。数值类型 MySQL支持所有标准SQL数值数据类型。日期和时间类型表示时间值的日期和时间类型为DATETIME、DATE、TIMESTAMP、TIME和YEAR。每个时间类型有一个有效值范围和一个"零"值，当指定不合法的MySQL不能表示的值时使用"零"值。字符串类型字符串类型指CHAR、VARCHAR、BINARY、VARBINARY、BLOB、TEXT、ENUM和SET。该节描述了这些类型如何工作以及如何在查询中使用这些类型。 CHAR 和 VARCHAR 类型类似，但它们保存和检索的方式不同。它们的最大长度和是否尾部空格被保留等方面也不同。在存储或检索过程中不进行大小写转换。 BINARY 和 VARBINARY 类似于 CHAR 和 VARCHAR，不同的是它们包含二进制字符串而不要非二进制字符串。也就是说，它们包含字节字符串而不是字符字符串。这说明它们没有字符集，并且排序和比较基于列值字节的数值值。 BLOB 是一个二进制大对象，可以容纳可变数量的数据

How to upload long blob (image) to mysql database using java and retrieve in php?

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问题 I am working on a project where I need to upload images to the database and retrieve the same from database. I need the image to be uploaded from an android device using java. Here is what i have implemented Bitmap bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), uri); // Log.d(TAG, String.valueOf(bitmap)); ByteArrayOutputStream stream = new ByteArrayOutputStream(); bitmap.compress(Bitmap.CompressFormat.PNG, 90, stream); //compress to which format you want. byte[] byte_arr =

Zip multiple database PDF blob files

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问题 I have a database table that contains numerous PDF blob files. I am attempting to combine all of the files into a single ZIP file that I can download and then print. Please help! <?php include '../config.php'; include '../connect.php'; $session = $_GET['session']; $query = "SELECT $tbl_uploads.username, $tbl_uploads.description, $tbl_uploads.type, $tbl_uploads.size, $tbl_uploads.content, $tbl_members.session FROM $tbl_uploads LEFT JOIN $tbl_members ON $tbl_uploads.username = $tbl_members

The limitation when getting blob data from oracle

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问题 I am trying the download the BLOB data from oracle with JDBC . In order to know the average response time of getting the blob data, I am using JMeter to call the Getting blob data Java program with one or multiply threads.But I got the strange response time I could not understand. I tried some tests below.(the blob data size is 1M) 1.Getting blob data with Jmeter in one thread 2.Getting blob data with Jmeter in two thread 3.Getting different blob data in the same table with JMeter in two

Can't display BLOB stored in database

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问题 I've got an problem when I want to convert an image in blob format stored in my database. When iç just echo $content I can actualy see the blob file printed out so there is no problem with my queries. The problem is that my code only displays an broken image instead of the Image in the database. Does anyone know how to display the image properly? Thanks in advance $content = mysql_result($result,$i,'Image'); echo '<img src="data:image/jpeg;base64,<?php echo base64_encode($content); ?>" width=

Get Image from Azure Blob using Proxy In Java

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问题 I need get Image from Azure blob storage container using Proxy and save the Image to BufferedImage. System.out.println("********Initiated******"); //Set Proxy Host name and Port Proxy proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress("xx-xx-xxxxx", 8080)); OperationContext op = new OperationContext(); op.setProxy(proxy); // Retrieve storage account from connection-string. CloudStorageAccount storageAccount = CloudStorageAccount.parse(storageConnectionString); // Create the blob client.

Keep javascript blob from editing data when saving file

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问题 I want to move data generated in javascript to a file I am using function saveTextAsFile(textToWrite,FileName){ var textFileAsBlob = new Blob([textToWrite], {type:'text/plain'}); var downloadLink = document.createElement("a"); downloadLink.download = FileName; downloadLink.innerHTML = "Download File"; if (window.webkitURL != null){ // Chrome allows the link to be clicked // without actually adding it to the DOM. downloadLink.href = window.webkitURL.createObjectURL(textFileAsBlob); } else{ //

Large character field sizes in SAS

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问题 I am trying to import a large blob field from a MySQL table via SAS ODBC passthrough. The field is larger than the maximum length allowed in SAS. According to SAS 9.2 documentation character type fields can have a maximum length of 32k. Has anyone had experience storing large character fields in SAS? Any suggestions other than the obvious one of breaking it down into smaller substrings? Thanks Rob 回答1: If you REALLY do need all 32K of that data to operate on, I would import it into more than