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SQL - many-to-many table primary key
...ving a primary key on (col1,col2) is guaranteed unique (assuming your col1 and col2 values in the referenced tables are unique) and a separate index on (col2,col1) will catch those cases where the opposite order would execute faster. The surrogate is a waste of space.
You won't need indexes on the ...
Can we use join for two different database tables?
...able names.
Let's suppose you have two databases on the same server - Db1 and Db2. Db1 has a table called Clients with a column ClientId and Db2 has a table called Messages with a column ClientId (let's leave asside why those tables are in different databases).
Now, to perform a join on the above-...
Should ol/ul be inside or outside?
Which is standard compliant between these two?
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Overriding Binding in Guice
I've just started playing with Guice, and a use-case I can think of is that in a test I just want to override a single binding. I think I'd like to use the rest of the production level bindings to ensure everything is setup correctly and to avoid duplication.
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How to get equal width of input and select fields
On the form, I have one select and two input fields. These elements are vertically aligned. Unfortunately, I can't get equal width of these elements.
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DROP IF EXISTS VS DROP?
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Standard SQL syntax is
DROP TABLE table_name;
IF EXISTS is not standard; different platforms might support it with different syntax, or not support it at all. In PostgreSQL, the syntax is
DROP TABLE IF EXISTS table_name;
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Rails 4: before_filter vs. before_action
...ore_filter.
However all before_filters syntax are deprecated in Rails 5.0 and will be removed in Rails 5.1
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jQuery slide left and show
I extended the jQuery effects called slideRightShow() and slideLeftHide() with a couple functions that work similarly to slideUp() and slideDown() as seen below. However, I would also like to implement slideLeftShow() and slideRightHide() .
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Add a new line in file?
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Check that you have "\n" and not '\n'
– Marklar
Dec 19 '12 at 11:12
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jQuery get the image src
I hope when I click the button, I can get the specific img src and show the img src in the div class img-block block.
5 A...