As was told at MySQL Using a string column with date text as a date field, you can do You can also handle these date strings in WHERE clauses. For example You can handle all kinds of date/time layouts this way. Please refer to the format specifiers for the DATE_FORMAT() function to see what you … Read more
I think this is what you’re looking for. NEW_BAL is the sum of QTYs subtracted from the balance: If you want to update the item balance with the new balance, use the following: This assumes you posted the subtraction backward; it subtracts the quantities in the order from the balance, which makes the most sense … Read more
I’m not professional in query writing, but wrote many from the time I began MySQL. Recently I noticed there is no need to type AS keyword in name aliasing. equals to However I know that this ability is out from years ago. I’ve 2 questions around this subject: Is AS keyword redundant? Sometimes ago when … Read more
A really easy way to do this is to add a UNIQUE index on the 3 columns. When you write the ALTER statement, include the IGNORE keyword. Like so: This will drop all the duplicate rows. As an added benefit, future INSERTs that are duplicates will error out. As always, you may want to take a backup before running something like this…
when you use x.name=y.name you are comparing country name from x with the country name from y if both instances have the same country name. That basically would just return you the full table x. You want to use x.continent=y.continent because you only want to compare the country name of an instance from x with the country name of … Read more
Someone here suggests that it might be a firewall problem: I have just had this problem and found it was my firewall. I use PCTools Firewall Plus and it wasn’t allowing full access to MySQL. Once I changed that it was fine. Hope that helps. Could that be it? Also, someone here suggests that it might be because the … Read more
Default sorting is ascending, you need to add the keyword DESC to both your orders:
It seems odd that this directory was not created at install – have you manually changed the path of the socket file in the my.cfg? Have you tried simply creating this directory yourself, and restarting the service?
Yes: You can use Inner Join to join on multiple columns. Create table Insert values
You could store the last insert id in a variable : Or get the max id from table1 (EDIT: Warning. See note in comments from Rob Starling about possible errors from race conditions when using the max id) (Warning: as Rob Starling points out in the