[Draft]add example sqlite

examples/mbrainz-sqlite/README.md

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+# About the mbrainz example
+
+This example demonstrates how mbrainz datomic database works with the 
+plenish. To use this example, we need to prepare the Datomic database
+and the empty sqlite database.
+
+## Prepare the Datomic database
+### Getting Datomic
+
+Follow the directs in your [My Datomic](http://my.datomic.com) account to 
+download a [Datomic distribution](http://www.datomic.com/get-datomic.html) and
+unzip it somewhere convenient.
+
+Update `config/samples/dev-transactor-template.properties` with your license key
+where you see`license=`.
+
+Start the transactor:
+
+    cd datomic-pro-$VERSION
+    bin/transactor config/samples/dev-transactor-template.properties
+
+### Getting the Data
+
+Next download the
+[subset of the mbrainz database](https://s3.amazonaws.com/mbrainz/datomic-mbrainz-1968-1973-backup-2017-07-20.tar)
+covering the period 1968-1973 (which the Datomic team has
+scientifically determined as being the most important period in the
+history of recorded music):
+
+    wget https://s3.amazonaws.com/mbrainz/datomic-mbrainz-1968-1973-backup-2017-07-20.tar -O mbrainz.tar
+    tar -xvf mbrainz.tar
+
+From the `datomic-pro-$VERSION` directory, [restore the backup](http://docs.datomic.com/on-prem/operation/backup.html#restoring):
+
+    # prints progress -- ~1,000 segments in restore
+    bin/datomic restore-db file://path/to/backup/mbrainz-1968-1973 datomic:dev://localhost:4334/mbrainz-1968-1973
+
+## Prepare the empty sqlite database
+
+1. Install sqlite CLI. Homebrew: `brew install sqlite`
+2. rm /tmp/mbrainz.db
+
+## Init the nREPL with Debug flag
+
+```
+export PLENISH_DEBUG=true &&  clj -M:dev:cider:sqlite:datomic-pro
+```
+
+## Results
+
+After running the commands in `src/lambdaisland/mbrainz.clj`, the tables in sqlite are
+

examples/mbrainz-sqlite/deps.edn

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+{:paths ["src" "resources"]
+
+ :deps
+ {org.clojure/clojure {:mvn/version "1.11.1"}
+  com.cnuernber/charred {:mvn/version "1.028"}
+  com.github.seancorfield/next.jdbc {:mvn/version "1.3.874"}
+  com.github.seancorfield/honeysql {:mvn/version "2.4.1026"}
+  com.lambdaisland/plenish {:local/root "../../" }}
+
+ :mvn/repos
+ {"my.datomic.com" {:url "https://my.datomic.com/repo"}}
+
+ :aliases
+ {:dev
+  {:extra-paths ["dev"]
+   :extra-deps  {com.lambdaisland/facai {:mvn/version "0.7.59-alpha"}
+                 djblue/portal {:mvn/version "RELEASE"}}}
+
+  :test
+  {:extra-paths ["test"]
+   :extra-deps  {lambdaisland/kaocha {:mvn/version "1.82.1306"}}}
+
+  :sqlite
+  {:extra-deps {org.xerial/sqlite-jdbc {:mvn/version "3.41.2.1"}}}
+
+  :datomic-pro
+  {:extra-deps {com.datomic/datomic-pro {:mvn/version "1.0.6202"}}}
+
+  :datomic-cloud
+  {:extra-deps {com.datomic/client-cloud {:mvn/version "1.0.123"}}}
+
+  :datomic-free
+  {:extra-deps  {com.datomic/datomic-free {:mvn/version "0.9.5703.21"}}}}}

examples/mbrainz-sqlite/src/lambdaisland/mbrainz.clj

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+(ns lambdaisland.mbrainz
+  (:require
+   [datomic.api :as d]
+   [lambdaisland.plenish :as plenish]
+   [next.jdbc :as jdbc]
+   [next.jdbc.result-set :as rs]))
+
+(def datomic-conn (d/connect "datomic:dev://localhost:4334/mbrainz-1968-1973"))
+(def sqlite-conn (jdbc/get-datasource "jdbc:sqlite:/tmp/mbrainz.db"))
+
+(def metaschema
+  {:tables {:release/name {}
+            :artist/name {}}})
+
+(def initial-ctx (plenish/initial-ctx datomic-conn metaschema))
+
+(def new-ctx (plenish/import-tx-range
+              initial-ctx datomic-conn sqlite-conn
+              (d/tx-range (d/log datomic-conn) nil nil)))