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Smallest data URI image possible for a transparent image
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After playing around with different transparent GIFs, some are unstable and cause CSS glitches. For example, if you have an <img> and you use the tiniest transparent GIF possible, it works fine, however, if you then want your transparent GIF to have a background-image, then this is im...
T-SQL: Deleting all duplicate rows but keeping one [duplicate]
I have a table with a very large amount of rows. Duplicates are not allowed but due to a problem with how the rows were created I know there are some duplicates in this table.
I need to eliminate the extra rows from the perspective of the key columns. Some other columns may have slightly different...
Pass column name in data.table using variable [duplicate]
In following example, I am creating a data table having column name ‘x’ and ‘v’
1 Answer
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Python: List vs Dict for look up table
I have about 10million values that I need to put in some type of look up table, so I was wondering which would be more efficient a list or dict ?
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Rails: How to list database tables/objects using the Rails console?
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You are probably seeking:
ActiveRecord::Base.connection.tables
and
ActiveRecord::Base.connection.columns('projects').map(&:name)
You should probably wrap them in shorter syntax inside your .irbrc.
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Setting DIV width and height in JavaScript
... </div>
<div id="div_register">
<table>
<tr>
<td>
welcome
</td>
</tr>
</table>
</div>
</body>
<...
How to keep indent for second line in ordered lists via CSS?
...ised to see this hasn't been solved yet. You can make use of the browser's table layout algorithm (without using tables) like this:
ol {
counter-reset: foo;
display: table;
}
ol > li {
counter-increment: foo;
display: table-row;
}
ol > li::before {
content: counter(foo) ...
When to use MyISAM and InnoDB? [duplicate]
...s better for beginners. No worries about the foreign relationships between tables.
Faster than InnoDB on the whole as a result of the simpler structure thus much less costs of server resources. -- Mostly no longer true.
Full-text indexing. -- InnoDB has it now
Especially good for read-intensive (se...
INNER JOIN vs LEFT JOIN performance in SQL Server
I've created SQL command that uses INNER JOIN on 9 tables, anyway this command takes a very long time (more than five minutes). So my folk suggested me to change INNER JOIN to LEFT JOIN because the performance of LEFT JOIN is better, despite what I know. After I changed it, the speed of query got si...
Swapping column values in MySQL
I have a MySQL table with coordinates, the column names are X and Y. Now I want to swap the column values in this table, so that X becomes Y and Y becomes X. The most apparent solution would be renaming the columns, but I don't want to make structure changes since I don't necessarily have permission...