How to find SQLITE database file version
You can write this command in any sqlite explorer which will give the sqlite version select sqlite_version();
database
Database vs File system storage
A database is generally used for storing related, structured data, with well defined data formats, in an efficient manner for insert, update and/or retrieval (depending on application). On the other hand, a file system is a more unstructured data store for storing arbitrary, probably unrelated data. The file system is more general, and databases are … Read more
CAP theorem – Availability and Partition Tolerance
Consistency means that data is the same across the cluster, so you can read or write from/to any node and get the same data. Availability means the ability to access the cluster even if a node in the cluster goes down. Partition tolerance means that the cluster continues to function even if there is a … Read more
Adding a new value to an existing ENUM Type
PostgreSQL 9.1 introduces ability to ALTER Enum types: ALTER TYPE enum_type ADD VALUE ‘new_value’; — appends to list ALTER TYPE enum_type ADD VALUE ‘new_value’ BEFORE ‘old_value’; ALTER TYPE enum_type ADD VALUE ‘new_value’ AFTER ‘old_value’;
List of standard lengths for database fields
I just queried my database with millions of customers in the USA. The maximum first name length was 46. I go with 50. (Of course, only 500 of those were over 25, and they were all cases where data imports resulted in extra junk winding up in that field.) Last name was similar to first … Read more
Need help in developing DB logic
Don’t use “smart keys”. This is a bad idea called “smart keys” or “encoding information in keys”. See this answer which contains this excerpt: Despite it now being easy to implement a Smart Key, it is hard to recommend that you create one of your own that isn’t a natural key, because they tend to … Read more
Personal names in a global application: What to store [closed]
There isn’t really a universal structured way to do this. I’d have a big field for “Full Name” and another field for “Display Name”. Both unicode. For example, in Spanish-speaking countries, IIRC, people usually have FOUR names. Two given names, and two surnames (one from the father, one from the mother). Arabs essentially have a … Read more
When we need to use 1-to-1 relationship in database design?
Vertical partitioning for large tables to reduce I/O and cache requirements — separate columns that are queried often vs rarely. Adding a column to a production system when the alter table is “too expensive”. Super-type/subtype pattern. Vertical partitioning to benefit from table (join) elimination — providing optimizer supports it (again to reduce I/O and cache) … Read more
Populating Spinner From SQLite Database Android
This is an old question but the first one I found when figuring out this issue. Here is a detailed explanation with full source which may cut some legwork. The answer is indeed to use a SimpleCursorAdapter which handles a list of strings but also has special handling for a matched ID field that gets … Read more