Added DELETE command

classes/delete.class.js

+const Query = require('./query.class');
+const { Pool } = require('pg');
+const { WhereMixin } = require('../mixins');
+
+/**
+ * Class for execution of DELETE queries
+ *
+ * @class Insert
+ */
+class Delete extends WhereMixin(Query) {
+  /**
+   * Creates an instance of Delete.
+   *
+   * @param {Pool} db
+   * @param {string} table
+   */
+  constructor(db, table) {
+    super(db);
+    this.table = table;
+  }
+
+  get query() {
+    return `DELETE FROM ${this.table} ${this.whereSQL}`;
+  }
+}
+
+module.exports = Delete;

classes/index.js

 module.exports = {
   Query: require('./query.class'),
   Select: require('./select.class'),
-  Insert: require('./insert.class')
+  Insert: require('./insert.class'),
+  Delete: require('./delete.class')
 };

classes/query.class.js

@@ -35,7 +35,7 @@ class Query {
    * @readonly
    */
   get canExecute() {
-    return this._query != '';
+    return this.query != '';
   }
 
   /**

index.js

 const { Pool } = require('pg');
-const { Query, Select, Insert } = require('./classes');
+const { Query, Select, Insert, Delete } = require('./classes');
 
 /**
  * Class for communication with PostgreSQL database
@@ -43,12 +43,23 @@ class DB {
 
   /**
    * Creates an Insert object
+   *
    * @param {string} table
    * @returns {Insert} insert
    */
   insert(table) {
     return new Insert(this._db, table);
   }
+
+  /**
+   * Creates a Delete object
+   *
+   * @param {string} table
+   * @returns {Delete} delete
+   */
+  delete(table) {
+    return new Delete(this._db, table);
+  }
 }
 
 module.exports = DB;

tests/test.js

@@ -11,10 +11,7 @@ const db = new DB({
 
 const select = async () => {
   console.log('SELECT');
-  const select = db
-    .select('lorem')
-    .columns('*')
-    .where('id > 2');
+  const select = db.select('lorem').columns('*');
 
   console.log(select.query);
   if (await select.execute()) {
@@ -37,11 +34,26 @@ const insert = async () => {
   }
 };
 
+const del = async () => {
+  console.log('DELETE');
+  const del = db.delete('lorem').where({ bar: 12 });
+
+  if (await del.execute()) {
+    console.log(del.rows);
+  } else {
+    console.log(del.err);
+  }
+};
+
 (async () => {
   await select();
   // await insert();
   // await select();
 
+  await del();
+
+  await select();
+
   process.exit();
 })();