Databases versus plain text

Question

When dealing with small projects, what do you feel is the break even point for storing data in simple text files, hash tables, etc., versus using a real database? For small

Answer 1

1) Concurrency. Do you have multiple people accessing the same dataset? Then it's going to get pretty involved to broker all of the different readers and writers in a scalable fashion if you roll your own system.

2) Formatting and relationships: Is your data something that doesn't fit neatly into a table structure? Long nucleotide sequences and stuff like that? That's not really conveniently tabular data.

Another example: Nobody would consider implementing software like Photoshop to store PSDs in a relational format, because the data structures don't really lend themselves to that type of storage or query pattern.

3) ACID (sort of a corollary to #1): If Atomicity, Consistency, Integrity, and Durability are not challenges with a flat file, then go with a flat file.