|  |  | @ -22,8 +22,8 @@ use yii\util\ArrayHelper; | 
			
		
	
		
		
			
				
					
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					|  |  |  |  * A migration means a set of persistent changes to the application environment |  |  |  |  * A migration means a set of persistent changes to the application environment | 
			
		
	
		
		
			
				
					
					|  |  |  |  * that is shared among different developers. For example, in an application |  |  |  |  * that is shared among different developers. For example, in an application | 
			
		
	
		
		
			
				
					
					|  |  |  |  * backed by a database, a migration may refer to a set of changes to the database, |  |  |  |  * backed by a database, a migration may refer to a set of changes to | 
			
				
				
			
		
	
		
		
			
				
					
					|  |  |  |  * such as creating a new table, adding a new table column. |  |  |  |  * the database, such as creating a new table, adding a new table column. | 
			
				
				
			
		
	
		
		
	
		
		
	
		
		
			
				
					
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					|  |  |  |  * This command provides support for tracking the migration history, upgrading |  |  |  |  * This command provides support for tracking the migration history, upgrading | 
			
		
	
		
		
			
				
					
					|  |  |  |  * or downloading with migrations, and creating new migration skeletons. |  |  |  |  * or downloading with migrations, and creating new migration skeletons. | 
			
		
	
	
		
		
			
				
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