Active 2 years, 5 months ago. Viewed 44k times. Improve this question. Oded Izkata Izkata 5, 5 5 gold badges 23 23 silver badges 43 43 bronze badges. At least for SQL Server , text is deprecated. There are also considerations of usage that are related to where the data is stored and how it therefore gets accessed.
On some DBMSs you may not be able to use a text column in a sort or where clause. I'm not familiar with Postgres but check your documentation. This StackOverflow question might provide some more info.
Add a comment. Active Oldest Votes. In General text columns are non standard and implementation specific. In Postgres All these types are internally saved using the same C data structure.
Use CHAR when you know you have a fixed number of characters for every entry. Improve this answer. Accepted for non standard and implementation specific and not indexable, not searchable and not sortable , which I didn't realize. I was under the impression text was standardized.
I haven't seen anything, some vendors call it long char and the like, it is basically a BLOB with an encoding attached to it. JarrodRoberson to be honest there are plenty of reputable resources that do conclude when in Postgres environment that "always use TEXT ". Their storage methods and data retrieval methods are different.
In terms of space occupancy, it is necessary to analyze the specific situation. Char is fixed length, varchar, text is variable length. When Char is saved, the back on the right will be filled with spaces to the specified length, and the back space will be removed during retrieval, so the retrieved data needs to be processed by any function such as trim.
May be slightly different from sql server. Varchar is not filled when it is saved. When the value is saved and retrieved, the trailing space remains. The TEXT column cannot have a default value, and there is no case conversion during storage or retrieval. When the stored characters exceed their defined length, if it is not in the strict mode of the SQL server, it will automatically intercept the appropriate field storage without error. Sign up to join this community. The best answers are voted up and rise to the top.
Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Ask Question. Asked 10 years, 10 months ago. Active 8 years, 1 month ago. Viewed 38k times. Improve this question. Derek Downey. Derek Downey Derek Downey Because the list there really does a good job of laying out the explicit details, and because you already have the enumerated list of differences, I'm not sure this is the sort of question we need on DBA.
Is there a reason that the list you cited and the reasons you gave aren't good enough in this case? I updated my question, but one obvious reason that I'm not sure on is performance of one over the other. If you need better performance, you have to use a fixed length type like CHAR. You can read more about this here. VARCHAR is faster when the size is reasonable, the tradeoff of which would be faster depends upon your data and your hardware, you'd want to benchmark a real-world scenario with your data.
Doing so makes it easier to format it according to the country of a visitor e. View this oft-reposted article.
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