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Does a UNIQUE constraint automatically create an INDEX on the field(s)?
...ally run into them.
As for testing index usage you should first fill your table with some data to make optimizer think it's actually worth to use that index.
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What does the KEY keyword mean?
In this MySQL table definition:
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PHP exec() vs system() vs passthru()
...egardless, I suggest you not use any of them. They all produce highly unportable code.
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Are negative array indexes allowed in C?
...want to use negative indexes, I have used them in two contexts:
Having a table of combinatorial numbers that tells you comb[1][-1] = 0; you can always check indexes before accessing the table, but this way the code looks cleaner and executes faster.
Putting a centinel at the beginning of a table. ...
htmlentities() vs. htmlspecialchars()
...ded with htmlentities.
implode( "\t", array_values( get_html_translation_table( HTML_ENTITIES ) ) ):
" & < >
¡ ¢ £ ¤ ¥ ¦ § ¨ © ª « ¬ ® ¯ ° ± ² ³ ´ µ ¶ · ¸ ¹ º » ¼ ½ ¾ ¿ À Á Â...
Get next / previous element using JavaScript?
... "formId" action="action.php" onsubmit="return false;">
<table>
<tr>
<td>
<label class="standard_text">E-mail</label>
</td>
<td><input class...
Simulate delayed and dropped packets on Linux
...bution to describe the variation in delay. The netem discipline can take a table to specify a non-uniform distribution.
# tc qdisc change dev eth0 root netem delay 100ms 20ms distribution normal
The actual tables (normal, pareto, paretonormal) are generated as part of the iproute2 compilation...
How do I create a readable diff of two spreadsheets using git diff?
... has a very cool feature to compare delimited data by showing it in a nice table, see screenshot.
D) You're now ready to compare Excel files with ease. Right-click on Excel file 1 and run your dump program. It will create a folder with one file per worksheet. Right-click on Excel file 2 and run you...
Sqlite LIMIT / OFFSET query
... necessarily mean it's in the order you want. The only way to get a predictable order is to use ORDER BY explicitly.
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What happens if you don't commit a transaction to a database (say, SQL Server)?
... looks from outside the transaction. Depending on the isolation level, the table may be locked until the first window is committed, or you might (not) see what the other transaction has done so far, etc.
Play around with the different isolation levels and no lock hint to see how they affect the res...