Is it possible to store whole keys / values ​​in LevelDB?

Question

I searched for key value stores that support integer keys and integer values. LevelDB seems like a good option, although I cannot find information on whether integer values ​​/ keys are supported

Answer 1

You can store almost everything in LevelDB. You provide opaque pieces of data to LevelDB through a structure Slice. Here is an example:

int intKey = 256;
int intValue = 256*256;

Slice key((char*)&intKey, sizeof(int));
Slice value((char*)&intValue, sizeof(int));

db->Put(leveldb::WriteOptions(), key, value);

And that is pretty much!

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Answer 2

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Answer 3

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Listing the keys in decimal and hex
 256 ( 100)
 512 ( 200)
 768 ( 300)
   1 (   1)
 257 ( 101)
 513 ( 201)
 769 ( 301)
   2 (   2)
 258 ( 102)
 514 ( 202)
 770 ( 302)
   3 (   3)
 259 ( 103)
 515 ( 203)
 771 ( 303)
...
 254 (  fe)
 510 ( 1fe)
 766 ( 2fe)
 255 (  ff)
 511 ( 1ff)
 767 ( 2ff)

Answer 4

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