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diff --git a/third_party/rust/rkv/examples/simple-store.rs b/third_party/rust/rkv/examples/simple-store.rs
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+++ b/third_party/rust/rkv/examples/simple-store.rs
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+// Any copyright is dedicated to the Public Domain.
+// http://creativecommons.org/publicdomain/zero/1.0/
+
+//! A simple rkv demo that showcases the basic usage (put/get/delete) of rkv.
+//!
+//! You can test this out by running:
+//!
+//!     cargo run --example simple-store
+
+use std::fs;
+
+use tempfile::Builder;
+
+use rkv::{
+    backend::{SafeMode, SafeModeDatabase, SafeModeEnvironment, SafeModeRwTransaction},
+    Manager, Rkv, StoreOptions, Value,
+};
+
+type MultiStore = rkv::MultiStore<SafeModeDatabase>;
+type Writer<'w> = rkv::Writer<SafeModeRwTransaction<'w>>;
+
+fn getput<'w, 's>(store: MultiStore, writer: &'w mut Writer, ids: &'s mut Vec<String>) {
+    let keys = vec!["str1", "str2", "str3"];
+    // we convert the writer into a cursor so that we can safely read
+    for k in keys.iter() {
+        // this is a multi-valued database, so get returns an iterator
+        let mut iter = store.get(writer, k).unwrap();
+        while let Some(Ok((_key, val))) = iter.next() {
+            if let Value::Str(s) = val {
+                ids.push(s.to_owned());
+            } else {
+                panic!("didn't get a string back!");
+            }
+        }
+    }
+    for id in ids {
+        store.put(writer, &id, &Value::Blob(b"weeeeeee")).unwrap();
+    }
+}
+
+fn delete(store: MultiStore, writer: &mut Writer) {
+    let keys = vec!["str1", "str2", "str3"];
+    let vals = vec!["string uno", "string quatro", "string siete"];
+    // we convert the writer into a cursor so that we can safely read
+    for i in 0..keys.len() {
+        store
+            .delete(writer, &keys[i], &Value::Str(vals[i]))
+            .unwrap();
+    }
+}
+
+fn main() {
+    let root = Builder::new().prefix("simple-db").tempdir().unwrap();
+    fs::create_dir_all(root.path()).unwrap();
+    let p = root.path();
+
+    // The manager enforces that each process opens the same lmdb environment at most once
+    let mut manager = Manager::<SafeModeEnvironment>::singleton().write().unwrap();
+    let created_arc = manager.get_or_create(p, Rkv::new::<SafeMode>).unwrap();
+    let k = created_arc.read().unwrap();
+
+    // Creates a store called "store"
+    let store = k.open_single("store", StoreOptions::create()).unwrap();
+    let multistore = k.open_multi("multistore", StoreOptions::create()).unwrap();
+
+    println!("Inserting data...");
+    {
+        // Use a writer to mutate the store
+        let mut writer = k.write().unwrap();
+        store.put(&mut writer, "int", &Value::I64(1234)).unwrap();
+        store
+            .put(&mut writer, "uint", &Value::U64(1234_u64))
+            .unwrap();
+        store
+            .put(&mut writer, "float", &Value::F64(1234.0.into()))
+            .unwrap();
+        store
+            .put(&mut writer, "instant", &Value::Instant(1_528_318_073_700))
+            .unwrap();
+        store
+            .put(&mut writer, "boolean", &Value::Bool(true))
+            .unwrap();
+        store
+            .put(&mut writer, "string", &Value::Str("héllo, yöu"))
+            .unwrap();
+        store
+            .put(
+                &mut writer,
+                "json",
+                &Value::Json(r#"{"foo":"bar", "number": 1}"#),
+            )
+            .unwrap();
+        store
+            .put(&mut writer, "blob", &Value::Blob(b"blob"))
+            .unwrap();
+        writer.commit().unwrap();
+    }
+
+    println!("Testing getput");
+    {
+        let mut ids = Vec::new();
+        let mut writer = k.write().unwrap();
+        multistore
+            .put(&mut writer, "str1", &Value::Str("string uno"))
+            .unwrap();
+        multistore
+            .put(&mut writer, "str1", &Value::Str("string dos"))
+            .unwrap();
+        multistore
+            .put(&mut writer, "str1", &Value::Str("string tres"))
+            .unwrap();
+        multistore
+            .put(&mut writer, "str2", &Value::Str("string quatro"))
+            .unwrap();
+        multistore
+            .put(&mut writer, "str2", &Value::Str("string cinco"))
+            .unwrap();
+        multistore
+            .put(&mut writer, "str2", &Value::Str("string seis"))
+            .unwrap();
+        multistore
+            .put(&mut writer, "str3", &Value::Str("string siete"))
+            .unwrap();
+        multistore
+            .put(&mut writer, "str3", &Value::Str("string ocho"))
+            .unwrap();
+        multistore
+            .put(&mut writer, "str3", &Value::Str("string nueve"))
+            .unwrap();
+        getput(multistore, &mut writer, &mut ids);
+        writer.commit().unwrap();
+        let mut writer = k.write().unwrap();
+        delete(multistore, &mut writer);
+        writer.commit().unwrap();
+    }
+
+    println!("Looking up keys...");
+    {
+        // Use a reader to query the store
+        let reader = k.read().unwrap();
+        println!("Get int {:?}", store.get(&reader, "int").unwrap());
+        println!("Get uint {:?}", store.get(&reader, "uint").unwrap());
+        println!("Get float {:?}", store.get(&reader, "float").unwrap());
+        println!("Get instant {:?}", store.get(&reader, "instant").unwrap());
+        println!("Get boolean {:?}", store.get(&reader, "boolean").unwrap());
+        println!("Get string {:?}", store.get(&reader, "string").unwrap());
+        println!("Get json {:?}", store.get(&reader, "json").unwrap());
+        println!("Get blob {:?}", store.get(&reader, "blob").unwrap());
+        println!(
+            "Get non-existent {:?}",
+            store.get(&reader, "non-existent").unwrap()
+        );
+    }
+
+    println!("Looking up keys via Writer.get()...");
+    {
+        let mut writer = k.write().unwrap();
+        store.put(&mut writer, "foo", &Value::Str("bar")).unwrap();
+        store.put(&mut writer, "bar", &Value::Str("baz")).unwrap();
+        store.delete(&mut writer, "foo").unwrap();
+        println!(
+            "It should be None! ({:?})",
+            store.get(&writer, "foo").unwrap()
+        );
+        println!("Get bar ({:?})", store.get(&writer, "bar").unwrap());
+        writer.commit().unwrap();
+        let reader = k.read().expect("reader");
+        println!(
+            "It should be None! ({:?})",
+            store.get(&reader, "foo").unwrap()
+        );
+        println!("Get bar {:?}", store.get(&reader, "bar").unwrap());
+    }
+
+    println!("Aborting transaction...");
+    {
+        // Aborting a write transaction rollbacks the change(s)
+        let mut writer = k.write().unwrap();
+        store.put(&mut writer, "foo", &Value::Str("bar")).unwrap();
+        writer.abort();
+
+        let reader = k.read().expect("reader");
+        println!(
+            "It should be None! ({:?})",
+            store.get(&reader, "foo").unwrap()
+        );
+        // Explicitly aborting a transaction is not required unless an early
+        // abort is desired, since both read and write transactions will
+        // implicitly be aborted once they go out of scope.
+    }
+
+    println!("Deleting keys...");
+    {
+        // Deleting a key/value also requires a write transaction
+        let mut writer = k.write().unwrap();
+        store.put(&mut writer, "foo", &Value::Str("bar")).unwrap();
+        store.delete(&mut writer, "foo").unwrap();
+        println!(
+            "It should be None! ({:?})",
+            store.get(&writer, "foo").unwrap()
+        );
+        writer.commit().unwrap();
+
+        // Committing a transaction consumes the writer, preventing you
+        // from reusing it by failing and reporting a compile-time error.
+        // This line would report error[E0382]: use of moved value: `writer`.
+        // store.put(&mut writer, "baz", &Value::Str("buz")).unwrap();
+    }
+
+    println!("Clearing store...");
+    {
+        // Clearing a store deletes all the entries in that store
+        let mut writer = k.write().unwrap();
+        store.put(&mut writer, "foo", &Value::Str("bar")).unwrap();
+        store.put(&mut writer, "bar", &Value::Str("baz")).unwrap();
+        store.clear(&mut writer).unwrap();
+        writer.commit().unwrap();
+
+        let reader = k.read().expect("reader");
+        println!(
+            "It should be None! ({:?})",
+            store.get(&reader, "foo").unwrap()
+        );
+        println!(
+            "It should be None! ({:?})",
+            store.get(&reader, "bar").unwrap()
+        );
+    }
+
+    println!("Write and read on multiple stores...");
+    {
+        let another_store = k
+            .open_single("another_store", StoreOptions::create())
+            .unwrap();
+        let mut writer = k.write().unwrap();
+        store.put(&mut writer, "foo", &Value::Str("bar")).unwrap();
+        another_store
+            .put(&mut writer, "foo", &Value::Str("baz"))
+            .unwrap();
+        writer.commit().unwrap();
+
+        let reader = k.read().unwrap();
+        println!(
+            "Get from store value: {:?}",
+            store.get(&reader, "foo").unwrap()
+        );
+        println!(
+            "Get from another store value: {:?}",
+            another_store.get(&reader, "foo").unwrap()
+        );
+    }
+}