Raster Data Support: Storage and processing of raster data, such as elevation data and weather data.Geometry Processing: Tools for processing and manipulating geometry data, such as simplification, conversion, and generalization.
Spatial Functions: A wide range of spatial functions that allow you to filter and analyze spatial data, measuring distances and areas, intersecting geometries, buffering, and more. Spatial Indexing: Quickly search and retrieve spatial data based on its location. Spatial Data Storage: Store different types of spatial data such as points, lines, polygons, and multi-geometries, in both 2D and 3D data. (OP's images are not small, so this is not really an answer to his question.PostGIS extends the capabilities of the PostgreSQL relational database by adding support storing, indexing and querying geographic data. This is definitely the right way to handle thumbnails. It can be simpler just to treat it as straight text just like all your other fields. Yes, I understand you could store the binary in the database and convert it to/from text on the way in and out of the database, but sometimes ORMs make that a hassle. Handling images as text also simplifies things when you have to send/receive json, which doesn't handle binary very well. In html, you can inline base64 in an tag, which can possibly simplify your app because you won't have to serve up the images as binary in a separate browser fetch. (See What is the space overhead of Base64 encoding?) Your database will be bigger, but the packets your webserver sends to the client won't be. The reason is that while base64 has an overhead of 33%, with compression that mostly goes away. If your images are small, consider storing them as base64 in a plain text field. But even then I tend to use the DB as the "master" storage for binaries, with all the other relations consistently linked, while providing some file system-based caching mechanism for performance optimization. However, true, reality is often too performance-demanding -), and it pushes you to serve the binary files from the file system. BTW, PostgreSQL is great in preserving consistency. It's such a benefit to be always sure about your data consistency, and to have the data "in one piece" (the DB). When images are not the only data you store, don't store them on the file system unless you absolutely have to. So, I prefer using pg_lo_*, you may guess. pg_dump provides "-b" option to include the large objects into the backup. Especially, when you store 4-6 MPix images. That helps in reducing the server memory footprint. Blobs, in contrast, you can stream into stdout. The question is stable '08 answer with 19 votes), please, help to improve this text.īytea being a "normal" column also means the value being read completely into memory when you fetch it. The input format is different from bytea, but the provided functions and operators are mostly the same", Manual.ĮDIT 2014: I have not changed the original text above today (my answer was Apr 22 '12, now with 14 votes), I am opening the answer for your changes (see "Wiki mode", you can edit!), for proofreading and for updates. NOTE2: remember that PostgreSQL have only bytea, not have a default Oracle's BLOB: "The SQL standard defines (.) BLOB. PostgreSQL have comparable performance and good tools for export/import/input/output. There are many advantages to using "only database" instead dual. NOTE1: today the use of "dual solutions" (database+filesystem) is deprecated (!). See also PostgreSQL binary data types manual, tests with bytea column, etc. Remember that it is a (unified) web-service, then can be stored at a separate database (with no backups), serving many tables. Apache modules): store thumbnails at file system may be better, compare performances. Database caching is the easiest way, but check your needs and server configs (ex. Cache also essential metadata, like width and height. Cache the little images to send it fast to the web-browser (to avoiding rendering problems) and reduce server processing. Use bytea (BYTE Array): for caching thumbnail images. 
Separating database is the best way for a "unified image webservice". In this case, I prefer bytea, but blob is near the same. Use a separate database with DBlink: for original image store, at another (unified/specialized) database. See Ivan's answer (no problem with backing up blobs!), PostgreSQL additional supplied modules, How-tos etc. Use blob (Binary Large OBject): for original image store, at your table. We need some distinction between "original image" and "processed image", like thumbnail.Īs Jcoby's answer says, there are two options, then, I recommend: Updating to 2012, when we see that image sizes, and number of images, are growing and growing, in all applications.
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