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rocksdb

2.6.0
3.1.1 3.1.0 3.0.0 2.6.2 2.6.1 retired 2.6.0 retired 2.5.0 2.4.1 2.4.0 2.3.0 2.2.0 2.1.0 2.0.0 1.9.0 1.8.0 1.7.0 1.6.0 1.5.1 1.5.0 1.4.0 1.3.2 1.3.1 1.3.0 1.2.0 1.1.1 1.1.0 1.0.0 0.26.2 0.26.1 0.26.0 0.25.0 0.24.0 0.23.3 0.23.2 0.23.1 0.23.0 0.22.0 0.21.0 0.20.1 0.20.0 0.19.0 0.18.0 0.17.0 0.16.0 0.15.0 0.14.0 0.13.1 0.13.0 0.12.0 0.11.0 0.10.0 0.9.1 0.9.0 0.8.2 0.8.1 0.8.0 0.7.1 0.7.0 0.6.4 0.6.3 0.6.2 0.6.1 0.6.0

RocksDB for Erlang

Retired package: Release invalid - Use 2.6.1 instead
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rocksdb guides counter_merge_operator.md
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guides/counter_merge_operator.md 

The counter operator allows you to maintain a counter. You can increase or decrease the counter with an integer value 



Ex:



```erlang



{ok, Db} = rocksdb:open("/tmp/rocksdb_merge_db.test",

                        [{create_if_missing, true},

                         {merge_operator, counter_merge_operator}]),



ok = rocksdb:merge(Db, <<"c">>, << "1" >>, []),

{ok, << "1" >>} = rocksdb:get(Db, <<"c">>, []),



ok = rocksdb:merge(Db, <<"c">>, << "2" >>, []),

{ok, << "3" >>} = rocksdb:get(Db, <<"c">>, []),



ok = rocksdb:merge(Db, <<"c">>, <<"-1">> , []),

{ok, <<"2">>} = rocksdb:get(Db, <<"c">>, []),



ok = rocksdb:put(Db, <<"c">>, <<"0">>, []),

{ok, <<"0">>} = rocksdb:get(Db, <<"c">>, []),





ok = rocksdb:close(Db),

```