Help: Overwrite a few bytes in large file
Posted on 1997-07-17
I am writing a database programme, it is require to handle a very large database file (about 10 MB).
It is quite hard for me to change only a few bytes in file. It is because the method I use is linear loading.
For Example, my db file have 6 element ABCDEF, If I want to overwrite E by Z (ABCDZF),
I need to
1, Read ABCD
2, Write ABCD
3, Write Z
4, skip reading E
5, Read F
6, Write F
7, Close the File
It is no problem, if the Database is so small, but my is too large for that operation, If everytime I just change 3 bytes in 10MB file at 9MB after the head of file. It will be too time consuming.
Is it possible to skip operation [1,2,5,6], but still can change E to Z?
Thanks for reading.