Add PL/pg SQL (without test support)

plpgsql/README.md

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+# Setup
+Create database structure: psql -f ./structure/create.sql
+Load code into database psql -f ./code/update_quality.sql -d gilded_rose
+Load test data into database: psql -f ./test/data/load.sql -d gilded_rose
+Execute: CALL update_quality();
+Check results: SELECT * FROM items;
+
+# Test
+No test code provided, only a sample of test data
+TODO: [https://pgtap.org/](introduce TAP - xUnit for PL/pg SQL)
+

plpgsql/code/update_quality.sql

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+CREATE OR REPLACE PROCEDURE public.update_quality()
+  LANGUAGE plpgsql
+AS $$
+
+DECLARE
+
+    rec_item   RECORD;
+    cur_items  CURSOR FOR SELECT * FROM item;
+    
+BEGIN
+
+OPEN cur_items;
+    
+    
+   LOOP
+
+      FETCH cur_items INTO rec_item;
+      EXIT WHEN NOT FOUND;
+ 
+      IF (rec_item.name <> 'Aged Brie' AND rec_item.name <> 'Backstage passes to a TAFKAL80ETC concert') THEN
+        IF (rec_item.quality > 0) THEN
+          IF (rec_item.name <> 'Sulfuras, Hand of Ragnaros') THEN
+            rec_item.quality = rec_item.quality - 1;
+          END IF;
+        END IF;
+      ELSE
+        IF (rec_item.quality < 50) THEN
+          rec_item.quality = rec_item.quality + 1;
+          IF (rec_item.name = 'Backstage passes to a TAFKAL80ETC concert') THEN
+            IF (rec_item.sellIn < 11)  THEN
+              IF (rec_item.quality < 50)  THEN
+                rec_item.quality = rec_item.quality + 1;
+              END IF;
+            END IF;
+            IF (rec_item.sellIn < 6) THEN
+              IF (rec_item.quality < 50) THEN
+                rec_item.quality = rec_item.quality + 1;
+              END IF;
+            END IF;
+          END IF;
+        END IF;
+      END IF;
+    
+      IF (rec_item.name <> 'Sulfuras, Hand of Ragnaros') THEN
+        rec_item.sellIn = rec_item.sellIn - 1;
+      END IF;
+      
+      IF (rec_item.sellIn < 0) THEN
+        IF (rec_item.name <> 'Aged Brie') THEN
+          IF (rec_item.name <> 'Backstage passes to a TAFKAL80ETC concert') THEN
+            IF (rec_item.quality > 0) THEN
+              IF (rec_item.name <> 'Sulfuras, Hand of Ragnaros') THEN
+                rec_item.quality = rec_item.quality - 1;
+              END IF;
+            END IF;
+          ELSE
+            rec_item.quality = rec_item.quality - rec_item.quality;
+          END IF;
+        ELSE
+          IF (rec_item.quality < 50) THEN
+            rec_item.quality = rec_item.quality + 1;
+          END IF;
+        END IF;
+      END IF;
+      
+      UPDATE item 
+      SET 
+        quality = rec_item.quality,
+        sellIn  = rec_item.sellIn
+      WHERE 
+        name = rec_item.name;
+
+   END LOOP;
+  
+   CLOSE cur_items;
+   
+  COMMIT;
+   
+END;
+$$

plpgsql/structure/create.sql

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+CREATE DATABASE gilded_rose;
+
+\connect gilded_rose;
+
+CREATE TABLE item (
+ name    CHARACTER VARYING(100) NOT NULL,
+ sellIn  INTEGER,
+ quality INTEGER                NOT NULL
+);

plpgsql/test/data/load.sql

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+\set AUTOCOMMIT off
+
+TRUNCATE TABLE item;
+
+INSERT INTO item (name, sellIn, quality) VALUES ('+5 Dexterity Vest', 10, 20);
+INSERT INTO item (name, sellIn, quality) VALUES ('Aged Brie', 2, 0);
+INSERT INTO item (name, sellIn, quality) VALUES ('Elixir of the Mongoose', 5, 7);
+INSERT INTO item (name, sellIn, quality) VALUES ('Sulfuras, Hand of Ragnaros', 0, 80);
+INSERT INTO item (name, sellIn, quality) VALUES ('Sulfuras, Hand of Ragnaros', -1, 80);
+INSERT INTO item (name, sellIn, quality) VALUES ('Backstage passes to a TAFKAL80ETC concert', 15, 20);
+INSERT INTO item (name, sellIn, quality) VALUES ('Backstage passes to a TAFKAL80ETC concert', 10, 49);
+INSERT INTO item (name, sellIn, quality) VALUES ('Backstage passes to a TAFKAL80ETC concert', 5, 49);
+
+-- this conjured item does not work properly yet
+INSERT INTO item (name, sellIn, quality) VALUES ('Conjured Mana Cake', 3, 6);
+
+COMMIT;