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Setting up foreign keys in phpMyAdmin?
I'm setting up a database using phpMyAdmin. I have two tables ( foo and bar ), indexed on their primary keys . I am trying to create a relational table ( foo_bar ) between them, using their primary keys as foreign keys.
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What's the difference between identifying and non-identifying relationships?
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An identifying relationship is when the existence of a row in a child table depends on a row in a parent table. This may be confusing because it's common practice these days to create a pseudokey for a child table, but not make the foreign key to the parent part of the child's primary key. Fo...
How to play audio?
...ats as HTML5’s <audio>. Wikipedia has a audio format compatibility table. new Audio() can play WAV files in all browsers except Internet Explorer.
– Rory O'Kane
Mar 15 '15 at 14:18
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Vertically centering a div inside another div [duplicate]
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tl;dr
Vertical align middle works, but you will have to use table-cell on your parent element and inline-block on the child.
This solution is not going to work in IE6 & 7. Yours is the safer way to go for those. But since you tagged your question with CSS3 and HTML5 I was thinkin...
Retrieve the maximum length of a VARCHAR column in SQL Server
I want to find the longest VARCHAR in a specific column of a SQL Server table.
10 Answers
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Why is require_once so bad to use?
... I doubt your defined() method is any faster than the built-in lookup table, but I agree with your overall point - surely a non-issue?!
– Bobby Jack
Oct 9 '08 at 8:42
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Find difference between timestamps in seconds in PostgreSQL
I have a table in PostgreSQL 8.3 with 2 timestamp columns. I would like to get the difference between these timestamps in seconds. Could you please help me how to get this done?
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Do I need to create indexes on foreign keys on Oracle?
I have a table A and a table B . A has a foreign key to B on B 's primary key, B_ID .
7 Answers
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What is the most ridiculous pessimization you've seen? [closed]
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Databases are pessimization playland.
Favorites include:
Split a table into multiples (by date range, alphabetic range, etc.) because it's "too big".
Create an archive table for retired records, but continue to UNION it with the production table.
Duplicate entire databases by (division/cus...
Order data frame rows according to vector with specific order
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Does anyone know a data.table version of this?
– Reilstein
Sep 23 '16 at 17:50
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