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Should each and every table have a primary key?
...ite.
If you have a many-to-many link table, you create the primary key on all fields involved in the link. Thus you ensure that you don't have two or more records describing one link.
Besides the logical consistency issues, most RDBMS engines will benefit from including these fields in a unique in...
How to deal with “java.lang.OutOfMemoryError: Java heap space” error?
...form you are running on. In Windows 32 bit this is around 2GB (not specifically heap but total amount of memory per process). It just happens that Java chooses to make the default smaller (presumably so that the programmer can't create programs that have runaway memory allocation without running int...
How to recover MySQL database from .myd, .myi, .frm files
...ith MySQL versions and any needed runs of the mysql_upgrade utility.)
Actually, you probably just need the .FRM (table structure) and .MYD (table data), but you'll have to repair table to rebuild the .MYI (indexes).
The only constraint is that if you're downgrading, you'd best check the release no...
What does the number in parentheses shown after Unix command names in manpages mean?
...he command is assigned to.
These are split as
General commands
System calls
C library functions
Special files (usually devices, those found in /dev) and drivers
File formats and conventions
Games and screensavers
Miscellanea
System administration commands and daemons
Original descriptions of e...
When should I use a trailing slash in my URL?
...
In my personal opinion trailing slashes are misused.
Basically the URL format came from the same UNIX format of files and folders, later on, on DOS systems, and finally, adapted for the web.
A typical URL for this book on a Unix-like operating system would be a file path such as...
How can I calculate the number of lines changed between two commits in git?
...e - that's a task for git log. Ron DeVera touches on this, but you can actually do a lot more than what he mentions. Since git log internally calls the diff machinery in order to print requested information, you can give it any of the diff stat options - not just --shortstat. What you likely want to...
Web workers without a separate Javascript file?
...n tell, web workers need to be written in a separate JavaScript file, and called like this:
25 Answers
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Set the table column width constant regardless of the amount of text in its cells?
...ny extra text from coming out of the table.
You should make sure to leave all of the bordering and sizing for CSS, too.
Ok so here's what I have:
table {
border: 1px solid black;
table-layout: fixed;
width: 200px;
}
th,
td {
border: 1px solid black;
width: 100px;
overfl...
Word wrapping in phpstorm
...
For all files (default setting for opened file): Settings/Preferences | Editor | General | Use soft wraps in editor
For currently opened file in editor: Menu | View | Active Editor | Use Soft Wraps
In latest IDE versions you ...
Excel “External table is not in the expected format.”
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"External table is not in the expected format." typically occurs when trying to use an Excel 2007 file with a connection string that uses: Microsoft.Jet.OLEDB.4.0 and Extended Properties=Excel 8.0
Using the following connection string seems to fix most problems.
public static...