50 lines
1006 B
Markdown
50 lines
1006 B
Markdown
# leveldb.nim
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[](https://zielmicha.github.io/leveldb.nim/)
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A LevelDB wrapper for Nim in a Nim friendly way.
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Create a database:
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```Nim
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import leveldb
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import options
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var db = leveldb.open("/tmp/mydata")
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```
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Read or modify the database content:
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```Nim
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assert db.getOrDefault("nothing", "") == ""
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db.put("hello", "world")
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db.put("bin", "GIF89a\1\0")
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echo db.get("hello")
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assert db.get("hello").isSome()
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var key, val = ""
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for key, val in db.iter():
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echo key, ": ", repr(val)
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db.delete("hello")
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assert db.get("hello").isNone()
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```
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Batch writes:
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```Nim
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let batch = newBatch()
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for i in 1..10:
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batch.put("key" & $i, $i)
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batch.delete("bin")
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db.write(batch)
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```
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Iterate over subset of database content:
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```Nim
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for key, val in db.iterPrefix(prefix = "key1"):
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echo key, ": ", val
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for key, val in db.iter(seek = "key3", reverse = true):
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echo key, ": ", val
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db.close()
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```
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