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Selecting element by data attribute
					Is there an easy and straight-forward method to select elements based on their  data  attribute?  For example, select all anchors that has data attribute named  customerID  which has value of  22 .  
                    
                    
                        
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							SQL join: selecting the last records in a one-to-many relationship
					... want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
                    
                    
                        
                            
                                
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							Select2 dropdown but allow new values by user?
					I want to have a dropdown with a set of values but also allow the user to "select" a new value not listed there. 
                    
                    
                        
                            
                                
                                        9 Answers...				
				
				
							SELECT * WHERE NOT EXISTS
					...uming these tables should be joined on employeeID, use the following:    
SELECT  *
FROM    employees e
WHERE   NOT EXISTS
        (
        SELECT  null 
        FROM    eotm_dyn d
        WHERE   d.employeeID = e.id
        )
You can join these tables with a LEFT JOIN keyword and filter out the...				
				
				
							1052: Column 'id' in field list is ambiguous
					...and  tbl_section  which has both the  id  field in them. How do I go about selecting the  id  field, because I always get this error:
                    
                    
                        
                            
                                
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							Why are Where and Select outperforming just Select?
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Select iterates once over the entire set and, for each item, performs a conditional branch (checking for validity) and a + operation.
Where+Select creates an iterator that skips invalid elements (doesn't yield them), perform...				
				
				
							jquery get all form elements: input, textarea & select
					Is there an easy way (without listing them all separately) in jquery to select all form elements and only form elements.
                    
                    
                        
                            
                                
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							Select rows which are not present in other table
					...task, all of them standard SQL.
NOT EXISTS
Often fastest in Postgres.  
SELECT ip 
FROM   login_log l 
WHERE  NOT EXISTS (
   SELECT  -- SELECT list mostly irrelevant; can just be empty in Postgres
   FROM   ip_location
   WHERE  ip = l.ip
   );
Also consider:
What is easier to read in EXISTS...				
				
				
							JComboBox Selection Change Listener?
					...istener() will work, too.  You may get 2 ItemEvents, though, one for the deselection of the previously selected item, and another for the selection of the new item. Just don't use both event types!
    
    
        
            
            
                
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							Difference between two dates in MySQL
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SELECT TIMEDIFF('2007-12-31 10:02:00','2007-12-30 12:01:01');
-- result: 22:00:59, the difference in HH:MM:SS format
SELECT TIMESTAMPDIFF(SECOND,'2007-12-30 12:01:01','2007-12-31 10:02:00'); 
-- result: 79259  the differenc...				
				
				
							