CONTACT US
568-3-53 (3rd Floor), Kompleks Mutiara, 3 1/2 Mile, Jalan Ipoh
51200 Kuala Lumpur, Malaysia
6012 9714904
support@yohz.com
https://www.yohz.com
Copyright © 2005 - 2023 Yohz Software,
a division of Yohz Ventures Sdn Bhd.
ALL RIGHTS RESERVED.
All trademarks or registered trademarks are property of their respective owners
View and export images and files from
your databases using
SQL Image Viewer
•
identifies images and file types automatically
•
identify images and files stored in OLE Object columns
•
export embedded images to Excel spreadsheets
•
supports Access, MySQL, MariaDB, Oracle, PostgreSQL,
SQL Server, SQL Server Compact, SQLite, and ODBC
data sources
How to export a large amount of images
In SQL Image Viewer, you usually run a SQL script to retrieve
the data set you want to export. For very large data sets,
retrieving the entire data set into your system's memory may
not be feasible or exceeds your hardware capacity.
For example, say you want to export a thousand images from
your database, and each image is around 5 MB in size. The
total size of the data set is then approximately 5 GB. Say your
system memory is only 4 GB. It's then not possible to export
the data set the usual way.
What you need to do is to tell SQL Image Viewer to just return
the first few rows of the data set, using the Return option. Say
you select 5 rows.
SQL Image Viewer then returns just the number of rows you
specify. It does not need to retrieve all 1000 images. It just
retrieves the first 5 rows and display the data, allowing you to
check if it's the data you want, and also to tell SQL Image
Viewer the columns that will be returned, so that you can use
them in your file naming convention.
Now, when you choose one of the export options, SQL Image
Viewer will still retrieve and export all 1000 images, but it does
this in batches. Say you choose the Export to text files option.
You will see the Batch size option in the top right. What this
value represents is the number of rows SQL Image Viewer
retrieves each time from your server.
In our example, a value of 20 means SQL Image Viewer will
retrieve only 20 rows each time (consuming approximately 100
MB of memory, as each image is 5 MB in size), export the 20
images to disk, discard the 20 rows, fetch the next 20 rows,
and repeat the process again. In this way, SQL Image Viewer
will only use a maximum of 100 MB to store the data set.
In this way, it doesn’t matter if you export 1000, 10000, or
1000000 rows - SQL Image Viewer will only ever hold 20 rows
in memory, and can export all your images and files easily
without being constrained by the available memory on your
system.
Generally, the larger the batch size, the faster the export
process, but consumes more memory. Thus, you have to
know the average row size, the RAM available on your system,
and work out the appropriate batch size.