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How to store arrays in MySQL?
... retrieve a person and all of their fruit you can do something like this:
SELECT p.*, f.*
FROM person p
INNER JOIN person_fruit pf
ON pf.person_id = p.id
INNER JOIN fruits f
ON f.fruit_name = pf.fruit_name
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How to handle click event in Button Column in Datagridview?
...ast the sender to type DataGridView, we can get the Columns collection and select the current column using e.ColumnIndex. Then check if that object is of type DataGridViewButtonColumn.
Of course, if you need to distinguish between multiple buttons per grid, you can then select based on the column n...
git - merge conflict when local is deleted but file exists in remote
...
In Git GUI, you select the conflicted file and then right-click on the main text area where the conflicted text is shown.
In the context menu that appears, you can choose to go with "Remote" or go with "Local". So if a file is remotely del...
How can I remove an SSH key?
...gether.
Go to System --> Preferences --> Startup Applications, and unselect the "SSH Key Agent (Gnome Keyring SSH Agent)" box -- you'll need to scroll down to find it.
You'll still get an ssh-agent, only now it will behave sanely: no keys autoloaded, you run ssh-add to add them, and if you w...
How do I force Postgres to use a particular index?
...d, client_id, date, and description. You want to run the following query:
SELECT client_id, SUM(amount)
FROM transactions
WHERE date >= 'yesterday'::timestamp AND date < 'today'::timestamp AND
description = 'Refund'
GROUP BY client_id
PostgreSQL may choose to use the index transaction...
How to search for occurrences of more than one space between words in a line
...
This regex selects all spaces, you can use this and replace it with a single space
\s+
example in python
result = re.sub('\s+',' ', data))
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In Intellij, how do I toggle between camel case and underscore spaced?
...g Manipulation which has the capabilities you're looking for (and more).
Select historyOfPresentIllness and press Alt+M to bring up the plugin menu, then press:
5 - To snake_case (or to camelCase) which converts to history_of_present_illness
6 - To hyphen-case (or to snake_case) which converts...
What is the difference between Step Into and Step Over in the Eclipse debugger?
...
Step Into The next expression on the currently-selected line to be executed is invoked, and execution suspends at the next executable line in the method that is invoked.
Step Over The currently-selected line is executed and suspends on the next executable line.
...
How to map a composite key with JPA and Hibernate?
... way you write queries (making them more or less verbose):
with IdClass
select t.levelStation from Time t
with EmbeddedId
select t.timePK.levelStation from Time t
References
JPA 1.0 specification
Section 2.1.4 "Primary Keys and Entity Identity"
Section 9.1.14 "EmbeddedId Annotation"
Sect...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
...the "General" tab.
Make sure you have the column you want to make unique selected in the "columns" box.
Change the "Type" box to "Unique Key".
Click "Close".
You see a little asterisk in the file window, this means changes are not yet saved.
Press Save or hit Ctrl+s. It should save, and your colu...