Oops, hit send to soon. Your second question has been discussed in the thread "IP from number with SQL" started on Sun, Mar 15, 2009 at 4:10 PM. Of course with the knowledge that IPv6 is just IPv4 with more bits thrown at it, you can tweak the discussion to suit your needs.
On Thu, Apr 2, 2009 at 8:54 AM, Rich Rattanni <ratta...@gmail.com> wrote: > Igor, be careful your not solving someone's homework.... > > On Thu, Apr 2, 2009 at 7:39 AM, Igor Tandetnik <itandet...@mvps.org> wrote: >> "My Name" <mylistuser1...@gmail.com> >> wrote in message >> news:ee8102080904012149h3b8d64d9u8b972b1e6fbbf...@mail.gmail.com >>> I'm having hard time to store and retrieve data with SQLite. Let's >>> assume I have this structure in my C code to hold my data >>> >>> struct foo { >>> long a; >>> float b; >>> char c[1024]; >>> int d; >>> } >>> >>> so the SQL definition would be >>> >>> CREATE TABLE foo >>> ( >>> a LONG; >>> b FLOAT; >>> c VARCHAR(1024); >>> d INT; >>> ); >>> >>> In real life c[1024] does not hold a printable string but variable >>> length binary data and d tells the data length. >> >> You probably want to store it as a BLOB then, not as text. You don't >> need a separate column for d - a BLOB column knows its length (and so >> does text, so you don't need extra column either way). >> >>> Let's also assume I >>> have N records where some of the fields can be same. >>> >>> { 1, 1.0, "data1", 5 } >>> { 1, 2.0, "data2", 5 } >>> { 2, 1.0, "data3", 5 } >>> { 2, 2.0, "data4", 5 } >>> { 5, 6.0, "data5", 5 } >>> >>> And here's the "dummy user" part, how should I read from and write to >>> the database? I want to execute >>> >>> DELETE FROM foo WHERE b < ... >>> INSERT INTO foo VALUE (......) >>> SELECT * FROM foo WHERE a=... AND b=... >>> SELECT c,d FROM foo WHERE a=... AND b=... >> >> sqlite3* db = NULL; >> sqlite3_open("myfile.db", &db); >> >> sqlite3_stmt* stmt = NULL; >> sqlite3_prepare_v2(db, "select * from foo where a=? and b=?;", &stmt, >> NULL); >> >> sqlite3_bind_int(stmt, 1, 42); >> sqlite3_bind_double(stmt, 2, 4.2); >> >> while (sqlite3_step(stmt) == SQLITE_ROW) { >> foo row; >> row.a = sqlite3_column_int(stmt, 0); >> row.b = sqlite3_column_double(stmt, 1); >> row.d = sqlite3_column_bytes(stmt, 2); >> assert(row.d <= sizeof(row.c)); >> memcpy(row.c, sqlite3_column_blob(stmt, 2), row.d); >> >> // do something with row >> } >> >> sqlite3_finalize(stmt); >> sqlite3_close(db); >> >> >> DELETE and INSERT are left as an exercise for the reader. They work the >> same way, except that you only need to call sqlite3_step once, and of >> course there are no column values to retrieve. >> >> Igor Tandetnik >> >> >> >> _______________________________________________ >> sqlite-users mailing list >> sqlite-users@sqlite.org >> http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users >> > _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
