add create or replace view for postgresql

CHANGELOG.md

@@ -1,6 +1,7 @@
 # Changes
 
 * 2.4.next in progress
+  * Add `:create-or-replace-view` to support PostgreSQL's lack of `IF NOT EXISTS` for `CREATE VIEW`.
   * Add `:select` with function call and alias example to README (PR [#502](https://github.com/seancorfield/honeysql/pull/502) [@markbastian](https://github.com/markbastian)).
   * Address [#497](https://github.com/seancorfield/honeysql/issues/497) by adding `:alias` special syntax. Documentation TBD.
   * Attempt to clarify the formatting behavior of the `:values` clause when used to produce column names.

doc/clause-reference.md

@@ -318,6 +318,18 @@ user=> (sql/format {:refresh-materialized-view [:concurrently :products]
 ["REFRESH MATERIALIZED VIEW CONCURRENTLY products WITH NO DATA"]
 ```
 
+PostgreSQL does not support `IF NOT EXISTS` on `CREATE VIEW` (it supports it on
+`CREATE MATERIALIZED VIEW`!) so HoneySQL also has `:create-or-replace-view`
+for this case:
+
+```clojure
+user=> (sql/format {:create-or-replace-view [:products]
+                    :select [:*]
+                    :from [:items]
+                    :where [:= :category "product"]})
+["CREATE OR REPLACE VIEW products AS SELECT * FROM items WHERE category = ?" "product"]
+```
+
 ## drop-table, drop-extension, drop-view, drop-materialized-view
 
 `:drop-table` et al can accept a single table (extension, view) name or a sequence of

src/honey/sql.cljc

@@ -29,7 +29,8 @@
         it uppercase and replaces - with space). "
   (:refer-clojure :exclude [format])
   (:require [clojure.string :as str]
-            [honey.sql.protocols :as p]))
+            [honey.sql.protocols :as p]
+            [honey.sql :as sql]))
 
 ;; default formatting for known clauses
 
@@ -410,6 +411,7 @@
               [sql' & params'] (when (or pair? big?)
                                  (cond (sequential? a)
                                        (let [[sqls params] (format-expr-list a {:aliased true})]
+                                         (println "sequential alias expression:" a)
                                          (into [(str/join " " sqls)] params))
                                        big? ; BigQuery support #281
                                        (reduce (fn [[sql & params] [k arg]]
@@ -1196,6 +1198,8 @@
          :create-extension (fn [_ x] (format-create :create :extension x nil))
          :with-columns    #'format-table-columns
          :create-view     (fn [_ x] (format-create :create :view x :as))
+         ;; postgresql lacks if not exists:
+         :create-or-replace-view (fn [_ x] (format-create :create :or-replace-view x :as))
          :create-materialized-view (fn [_ x] (format-create :create :materialized-view x :as))
          :drop-table      #'format-drop-items
          :drop-extension  #'format-drop-items
@@ -2115,4 +2119,10 @@
                      :from :b
                      :order-by [[[:alias "some-alias"]]]}
                     {:quoted true})
+  (honey.sql/format {:select [[:column-name "some-alias"]]
+                     :from :b
+                     :order-by [[[:alias "some-alias"]]]}
+                    {:dialect :mysql})
+  (sql/format {:select :f.* :from [[:foo [:f :FOR :SYSTEM-TIME]]] :where [:= :f.id 1]})
+  (sql/format {:using [[:source [:= :table.id :source.id]]]})
   )