| sqlite driver manual: A libdbi driver using the SQLite embedded database engine | ||
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| Prev | Chapter 4. Peculiarities you should know about | |
And now we have to discuss how successful the sqlite driver is in squeezing the SQLite idea of a database engine into the libdbi framework which was shaped after MySQL and PostgreSQL. Keep in mind that the limitations mentioned here are not intrinsic, that is a sufficient amount of coding might fix these problems eventually.
The sqlite driver has not been tested for memory leaks yet. It may leak memory like hell.
The typeless nature of SQLite has some nasty consequences. The sqlite driver takes great care to reconstruct the type of a field that you request in a query, but this isn't always successful. Some of the functions that SQLite supports work both on numeric and text data. The sqlite driver currently cannot deduce the field type correctly as it would have to check all arguments of each function. Instead the sqlite driver makes a few assumptions that may be right or wrong in a given case. The affected functions are coalesce(X,Y,...), max(X), min(X), and count(X).
The sqlite driver currently assumes that the directory separator of your filesystem is a slash (/). This may be wrong on your particular system. It is not a problem for Windows systems as long as the sqlite driver is built with the Cygwin tools (see README.win32).
Note: Building the sqlite driver on Windows/Cygwin has not been tested yet, but it uses the same procedure as the other libdbi drivers. Chances are that it works.
Listing tables with the dbi_conn_get_table_list() libdbi function currently returns only permanent tables. Temporary tables are ignored.
The sqlite driver assumes that table and field names do not exceed 128 characters in length, including the trailing \0. I don't know whether SQLite internally has such a limit or not (both MySQL and PostgreSQL have a lower limit). The limit can be increased by changing a single #define in the dbd_sqlite.h header file.
In a few cases, the sqlite driver expects you to type SQL keywords in all lowercase or all uppercase, but not mixed. This holds true for the 'from' in a SELECT statement. Type it either as 'from' or as 'FROM', but refrain from using 'fRoM' or other funny mixtures of uppercase and lowercase. Most other database engines treat the keywords as case-insensitive and would accept all variants.