[ai.z7/libpg-clj "0.1.0"]DKD commons for PostgreSQL written in Clojure. The matter is to make PG interactions more frictionless.
[ai.z7/libpg-clj "0.1.0"]ai.z7/libpg-clj {:mvn/version "0.1.0"}(require '[libpg-clj.core :as pg])
(def pool (pg/make-pool {:classname "org.postgresql.Driver"
:subprotocol "postgresql"
:subname "//localhost:5432/mydb"
:user "postgres"
:password "secret"
:min-pool 2
:max-pool 10}))
;; Use with clojure.java.jdbc
(require '[clojure.java.jdbc :as jdbc])
(jdbc/query pool ["SELECT * FROM users"])
;; Close when done
(pg/close-pool pool)The connection pool implements Closeable, so you can use it with with-open for automatic resource management:
(with-open [pool (pg/make-pool config)]
(jdbc/query pool ["SELECT * FROM users"]))
;; Pool is automatically closed when exiting the blockmake-poolCreates a c3p0 connection pool for PostgreSQL.
(make-pool {:classname "org.postgresql.Driver"
:subprotocol "postgresql"
:subname "//localhost:5432/mydb"
:user "postgres"
:password "secret"
:min-pool 2
:max-pool 10
:prepare-threshold 0}) ; optional, default 0Returns a ConnectionPool record (implements Closeable) with :datasource key, suitable for use with clojure.java.jdbc and with-open.
close-poolCloses a connection pool, releasing all resources.
(close-pool pool)
;; Equivalent to:
(.close pool)
;; Or use with-open for automatic cleanupconvert-enumConverts a field value to a [value type] pair for enum casting in queries.
(def type-map {:status "user_status"})
(convert-enum :status type-map {:status "active" :name "John"})
;=> {:status ["active" "user_status"] :name "John"}add-time-labelAdds a UUID v1 timestamp to a map (useful for time-ordered identifiers).
(add-time-label {:name "test"} :created-at)
;=> {:name "test" :created-at #uuid "..."}jdbc-execExecutes a query and returns the first result (typically row count).
(jdbc-exec pool ["UPDATE users SET active = true WHERE id = ?" 123])
;=> 1explain-enumRetrieves all possible values for a PostgreSQL enum type.
(explain-enum pool "user_status")
;=> ["active" "inactive" "pending"]kw→pgenumConverts a namespaced keyword to a PostgreSQL enum. The namespace becomes the type (with - replaced by _), and the name becomes the value.
(kw->pgenum :user-status/active)
;=> PGobject with type="user_status" value="active"This conversion happens automatically when using namespaced keywords as values in queries.
h-castCreates a PostgreSQL cast expression for HoneySQL.
(h-cast :my-field :integer)
;=> Generates: my_field::integertotalA raw SQL window function for counting total rows (useful for pagination).
{:select [:id :name total]
:from [:users]
:limit 10}
;=> SELECT id, name, COUNT(*) OVER () FROM users LIMIT 10json-aggWraps a subquery with JSON aggregation.
(json-agg {:select [:id :name] :from [:users]})
;=> SELECT json_agg(x) FROM (SELECT id, name FROM users) xThis library extends HoneySQL with PostgreSQL-specific operators:
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Two convenience functions for JSONB field access:
json> - Returns JSON (preserves type);; Single key
(json> :data :name) ; data::jsonb->'name'
;; Path access
(json> :data [:user :name]) ; data::jsonb#>'{user,name}'
;; With cast
(json> :data :age :integer) ; (data::jsonb->'age')::integerjson>> - Returns text (always string);; Single key
(json>> :data :name) ; data::jsonb->>'name'
;; Path access
(json>> :data [:user :name]) ; data::jsonb#>>'{user,name}'
;; With cast
(json>> :data :count :integer) ; (data::jsonb->>'count')::integerNamespaced keywords are automatically converted to PostgreSQL enums:
;; This query:
{:insert-into :users
:values [{:name "John" :status :user-status/active}]}
;; Automatically converts :user-status/active to a PGobject
;; with type "user_status" and value "active"JSONB and JSON columns are automatically parsed into Clojure data structures:
;; If users.metadata is JSONB containing {"role": "admin"}
(jdbc/query pool ["SELECT metadata FROM users WHERE id = ?" 1])
;=> [{:metadata {:role "admin"}}]The libpg-clj.debug namespace provides query debugging tools:
print-statementPrints a prepared statement with bound parameters.
(require '[libpg-clj.debug :as debug])
(debug/print-statement pool ["SELECT * FROM users WHERE id = ?" 123])
;; Prints the PreparedStatement objectquery-explainRuns EXPLAIN ANALYZE on a query and pretty-prints the execution plan.
(debug/query-explain pool ["SELECT * FROM users WHERE id = ?" 123])
;; Prints the query execution planDistributed under the MIT License.
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