(docs) #4768 Add schema examples for migrations (#6304)

Reverted removeColumn value changes

(docs) #4768 Add schema examples for migrations

(docs) #4768 Add schema examples for migrations

docs/docs/migrations.md

@@ -119,8 +119,9 @@ queryInterface.createTable(
     }
     }
   },
   },
   {
   {
-    engine: 'MYISAM', // default: 'InnoDB'
-    charset: 'latin1' // default: null
+    engine: 'MYISAM',                     // default: 'InnoDB'
+    charset: 'latin1',                    // default: null
+    schema: 'public'                      // default: public, PostgreSQL only.
   }
   }
 )
 )
 ```
 ```
@@ -182,7 +183,7 @@ queryInterface.describeTable('Person').then(function(attributes) {
 })
 })
 ```
 ```
 
 
-### addColumn(tableName, attributeName, dataTypeOrOptions, options)
+### addColumn(tableNameOrOptions, attributeName, dataTypeOrOptions, options)
 
 
 This method allows adding columns to an existing table. The data type can be simple or complex.
 This method allows adding columns to an existing table. The data type can be simple or complex.
 
 
@@ -203,14 +204,32 @@ queryInterface.addColumn(
     allowNull: false
     allowNull: false
   }
   }
 )
 )
+
+// or with an explicit schema:
+
+queryInterface.addColumn({
+    tableName: 'Person',
+    schema: 'public'
+  },
+  'signature',
+  Sequelize.STRING
+)
+
 ```
 ```
 
 
-### removeColumn(tableName, attributeName, options)
+### removeColumn(tableNameOrOptions, attributeName, options)
 
 
 This method allows deletion of a specific column of an existing table.
 This method allows deletion of a specific column of an existing table.
 
 
 ```js
 ```js
 queryInterface.removeColumn('Person', 'signature')
 queryInterface.removeColumn('Person', 'signature')
+
+// or with an explicit schema:
+
+queryInterface.removeColumn({
+  tableName: 'Person',
+  schema: 'public'
+}, 'signature');
 ```
 ```
 
 
 ### changeColumn(tableName, attributeName, dataTypeOrOptions, options)
 ### changeColumn(tableName, attributeName, dataTypeOrOptions, options)