Query based insertion or updating of blob values
You must have a query that has an EXPLAIN which includes 'using temporary'.If 'using temporary' is shown in your EXPLAIN plan, then a temporary table is being created either in MEMORY or as My ISAM table on disk.This is in contrast to all other data types, for which storage is allocated once per column when the table is opened.In some cases, it may be desirable to store binary data such as media files in columns.If the table goes to disk as My ISAM instead of being a MEMORY Table, Created_tmp_disk_tables is also incremented by one, as seen here. The test table I used is using the My SQL world database andmysql alter table kris add primary key (id); The test query shown above is 'using temporary' because I group by one column and order by another, forcing My SQL to use a temporary table.Had I been using the same query on the original City table from the world database, a tmp table would have been needed as well, but it would have been created as a MEMORY table as the original name column is a CHAR(35).
Truly, I was getting Error 1048 was because I needed to use forward slashes!SOLUTION: In addition to proper permissions, I need to use "/", not "\" in path to blob data (which was a picture).Note, this worked properly even for a non-relative path starting at the drive letter!You may find My SQL's string handling functions useful for working with such data. For security and other reasons, it is usually preferable to do so using application code rather than giving application users the PDF (US Ltr) - 37.9Mb PDF (A4) - 37.9Mb PDF (RPM) - 32.9Mb HTML Download (TGZ) - 8.0Mb HTML Download (Zip) - 8.1Mb HTML Download (RPM) - 6.9Mb Man Pages (TGZ) - 132.7Kb Man Pages (Zip) - 189.0Kb Info (Gzip) - 3.4Mb Info (Zip) - 3.4Mb My SQL Backup and Recovery My SQL Globalization My SQL Information Schema My SQL Installation Guide Security in My SQL Starting and Stopping My SQL My SQL and Linux/Unix My SQL and Windows My SQL and OS X Building My SQL from Source My SQL Restrictions and Limitations My SQL Partitioning My SQL Secure Deployment Guide My SQL Tutorial My SQL Performance Schema My SQL Replication Using the My SQL Yum Repository A pratical example of how write and read images into My SQL tables,using Trolltech Qt4/C This example is for who reads/record images in tables using fields BLOB.First: Create a table, for example: CREATE TABLE picture ( ID INTEGER AUTO_INCREMENT, IMAGE BLOB, PRIMARY KEY (ID)) ENGINE=Inno DB;2) To read a image to a QByte Array QString file Name = "IMAGE.
(You will get Error 1048 if you try to insert a NULL value, or when using LOAD_FILE and it can't read it for any reason..always permissions.)2) After solving #1, SELECT statement seemed to confirm the picture is indeed stored in the table.