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Rewrite builders as records

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This seems to be very slightly faster than using `reify`. Also rename 
the map builder to `as-maps` and add unqualified variants of builders.
This commit is contained in:
Sean Corfield 2019-04-18 08:12:12 -07:00
parent 90a4b7d727
commit e5ea6af959
1 changed files with 72 additions and 71 deletions
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143
src/next/jdbc/result_set.clj
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@ -21,23 +21,18 @@
(set! *warn-on-reflection* true)
(defn get-column-names
"Given ResultSetMetaData, return a vector of columns names, each qualified by
the table from which it came.
If :identifiers was specified, apply that to both the table qualifier
and the column name."
"Given ResultSetMetaData, return a vector of column names, each qualified by
the table from which it came."
[^ResultSetMetaData rsmeta opts]
(let [idxs (range 1 (inc (.getColumnCount rsmeta)))]
(if-let [ident-fn (:identifiers opts)]
(mapv (fn [^Integer i]
(keyword (when-let [qualifier (not-empty (.getTableName rsmeta i))]
(ident-fn qualifier))
(ident-fn (.getColumnLabel rsmeta i))))
idxs)
(mapv (fn [^Integer i]
(keyword (not-empty (.getTableName rsmeta i))
(.getColumnLabel rsmeta i)))
idxs))))
(mapv (fn [^Integer i] (keyword (not-empty (.getTableName rsmeta i))
(.getColumnLabel rsmeta i)))
(range 1 (inc (.getColumnCount rsmeta)))))
(defn get-unqualified-column-names
"Given ResultSetMetaData, return a vector of unqualified column names."
[^ResultSetMetaData rsmeta opts]
(mapv (fn [^Integer i] (keyword (.getColumnLabel rsmeta i)))
(range 1 (inc (.getColumnCount rsmeta)))))
(defprotocol ReadableColumn
"Protocol for reading objects from the java.sql.ResultSet. Default
@ -82,42 +77,49 @@
(with-row [_ rs row])
(rs! [_ rs]))
(defn map-row-builder
"Given a ResultSet and options, return a RowBuilder that produces
bare hash map rows."
[^ResultSet rs opts]
(let [rsmeta (.getMetaData rs)
cols (get-column-names rsmeta opts)]
(reify
RowBuilder
(->row [this] (transient {}))
(column-count [this] (count cols))
(with-column [this row i]
(assoc! row
(nth cols (dec i))
(read-column-by-index (.getObject rs ^Integer i) rsmeta i)))
(row! [this row] (persistent! row)))))
(defrecord MapResultSetBuilder [^ResultSet rs rsmeta cols]
RowBuilder
(->row [this] (transient {}))
(column-count [this] (count cols))
(with-column [this row i]
(assoc! row
(nth cols (dec i))
(read-column-by-index (.getObject rs ^Integer i) rsmeta i)))
(row! [this row] (persistent! row))
ResultSetBuilder
(->rs [this] (transient []))
(with-row [this mrs row]
(conj! mrs row))
(rs! [this mrs] (persistent! mrs)))
(defn map-rs-builder
(defn as-maps
"Given a ResultSet and options, return a RowBuilder and ResultSetBuilder
that produces bare vectors of hash map rows."
[^ResultSet rs opts]
(let [rsmeta (.getMetaData rs)
cols (get-column-names rsmeta opts)]
(reify
RowBuilder
(->row [this] (transient {}))
(column-count [this] (count cols))
(with-column [this row i]
(assoc! row
(nth cols (dec i))
(read-column-by-index (.getObject rs ^Integer i) rsmeta i)))
(row! [this row] (persistent! row))
ResultSetBuilder
(->rs [this] (transient []))
(with-row [this rs row]
(conj! rs row))
(rs! [this rs] (persistent! rs)))))
(->MapResultSetBuilder rs rsmeta cols)))
(defn as-unqualified-maps
"Given a ResultSet and options, return a RowBuilder and ResultSetBuilder
that produces bare vectors of hash map rows, with simple keys."
[^ResultSet rs opts]
(let [rsmeta (.getMetaData rs)
cols (get-unqualified-column-names rsmeta opts)]
(->MapResultSetBuilder rs rsmeta cols)))
(defrecord ArrayResultSetBuilder [^ResultSet rs rsmeta cols]
RowBuilder
(->row [this] (transient []))
(column-count [this] (count cols))
(with-column [this row i]
(conj! row (read-column-by-index (.getObject rs ^Integer i) rsmeta i)))
(row! [this row] (persistent! row))
ResultSetBuilder
(->rs [this] (transient [cols]))
(with-row [this ars row]
(conj! ars row))
(rs! [this ars] (persistent! ars)))
(defn as-arrays
"Given a ResulSet and options, return a RowBuilder and ResultSetBuilder
@ -125,18 +127,16 @@
[^ResultSet rs opts]
(let [rsmeta (.getMetaData rs)
cols (get-column-names rsmeta opts)]
(reify
RowBuilder
(->row [this] (transient []))
(column-count [this] (count cols))
(with-column [this row i]
(conj! row (read-column-by-index (.getObject rs ^Integer i) rsmeta i)))
(row! [this row] (persistent! row))
ResultSetBuilder
(->rs [this] (transient [cols]))
(with-row [this rs row]
(conj! rs row))
(rs! [this rs] (persistent! rs)))))
(->ArrayResultSetBuilder rs rsmeta cols)))
(defn as-unqualified-arrays
"Given a ResulSet and options, return a RowBuilder and ResultSetBuilder
that produces a vector of simple column names followed by vectors of row
values."
[^ResultSet rs opts]
(let [rsmeta (.getMetaData rs)
cols (get-unqualified-column-names rsmeta opts)]
(->ArrayResultSetBuilder rs rsmeta cols)))
(declare navize-row)
@ -166,7 +166,7 @@
Supports Seqable which realizes a full row of the data."
[^ResultSet rs opts]
(let [gen (delay ((get :gen-fn opts map-row-builder) rs opts))]
(let [gen (delay ((get :gen-fn opts as-maps) rs opts))]
(reify
clojure.lang.ILookup
@ -208,11 +208,12 @@
(extend-protocol
DatafiableRow
clojure.lang.IObj
java.util.Map ; assume we can "navigate" any kind of hash map for now
(datafiable-row [this connectable opts]
(with-meta
this
{`core-p/datafy (navize-row connectable opts)})))
(with-meta this
{`core-p/datafy (navize-row connectable opts)}))
clojure.lang.IObj ; but we cannot "navigate" other things
(datafiable-row [this connectable opts] this))
(defn- stmt->result-set
"Given a PreparedStatement and options, execute it and return a ResultSet
@ -262,7 +263,7 @@
(rest sql-params)
opts)]
(if-let [rs (stmt->result-set stmt opts)]
(let [gen-fn (get opts :gen-fn map-row-builder)
(let [gen-fn (get opts :gen-fn as-maps)
gen (gen-fn rs opts)]
(when (.next rs)
(datafiable-row (row-builder gen) this opts)))
@ -273,7 +274,7 @@
(rest sql-params)
opts)]
(if-let [rs (stmt->result-set stmt opts)]
(let [gen-fn (get opts :gen-fn map-rs-builder)
(let [gen-fn (get opts :gen-fn as-maps)
gen (gen-fn rs opts)]
(loop [rs' (->rs gen) more? (.next rs)]
(if more?
@ -301,7 +302,7 @@
opts)]
(if-let [rs (stmt->result-set stmt opts)]
(when (.next rs)
(datafiable-row (row-builder (map-row-builder rs opts)) this opts))
(datafiable-row (row-builder (as-maps rs opts)) this opts))
{:next.jdbc/update-count (.getUpdateCount stmt)}))))
(-execute-all [this sql-params opts]
(with-open [con (p/get-connection this opts)]
@ -310,7 +311,7 @@
(rest sql-params)
opts)]
(if-let [rs (stmt->result-set stmt opts)]
(let [gen-fn (get opts :gen-fn map-rs-builder)
(let [gen-fn (get opts :gen-fn as-maps)
gen (gen-fn rs opts)]
(loop [rs' (->rs gen) more? (.next rs)]
(if more?
@ -331,12 +332,12 @@
(-execute-one [this _ opts]
(if-let [rs (stmt->result-set this (assoc opts :return-keys true))]
(when (.next rs)
(datafiable-row (row-builder (map-row-builder rs opts))
(datafiable-row (row-builder (as-maps rs opts))
(.getConnection this) opts))
{:next.jdbc/update-count (.getUpdateCount this)}))
(-execute-all [this sql-params opts]
(if-let [rs (stmt->result-set this opts)]
(let [gen-fn (get opts :gen-fn map-rs-builder)
(let [gen-fn (get opts :gen-fn as-maps)
gen (gen-fn rs opts)]
(loop [rs' (->rs gen) more? (.next rs)]
(if more?
@ -379,7 +380,7 @@
in the <table> portion of their name, the key is called 'id', and the
cardinality is :one.
Rows are looked up using 'execute!' or 'execute-one!' and the :entities
Rows are looked up using 'execute!' or 'execute-one!' and the :table-fn
function, if provided, is applied to both the assumed table name and the
assumed foreign key column name."
[connectable opts]
@ -390,7 +391,7 @@
(default-schema k))]
(if fk
(try
(let [entity-fn (:entities opts identity)
(let [entity-fn (:table-fn opts identity)
exec-fn! (if (= :many cardinality)
p/-execute-all
p/-execute-one)]