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MySQL indexes - what are the best practices?
...going on.
Broadly speaking, an index imposes an ordering on the rows of a table.
For simplicity's sake, imagine a table is just a big CSV file. Whenever a row is inserted, it's inserted at the end. So the "natural" ordering of the table is just the order in which rows were inserted.
Imagine y...
REST URI convention - Singular or plural name of resource while creating it
...from our database schema. And database standards tend to advocate singular table names, so we're going with that, but still under the same logic as this answer.
– André C. Andersen
Nov 24 '17 at 12:01
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For each row return the column name of the largest value
...partment name, rather than the number of roster counts, from the frequency table. A simple example below (column names = departments, row names = employee ids).
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How do I size a UITextView to its content?
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Tested on iOS 7 to resize an UITextView into an UITableViewCell. Works really great. This is the only answer that finally worked for me. Thanks!
– Alex
Nov 30 '13 at 18:40
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Is there any performance gain in indexing a boolean field?
...is is not entirely correct, without an index mySql needs to scan the whole table to find the relevant rows.
– ilanco
May 9 '12 at 22:04
4
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What is the difference between “word-break: break-all” versus “word-wrap: break-word” in CSS
...at the container width — especially if the container is a pre element or table cell where the word-wrap property may not work as expected.
– gfullam
Jun 2 '15 at 18:50
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How to check which locks are held on a table
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You can find current locks on your table by following query.
USE yourdatabase;
GO
SELECT * FROM sys.dm_tran_locks
WHERE resource_database_id = DB_ID()
AND resource_associated_entity_id = OBJECT_ID(N'dbo.yourtablename');
See sys.dm_tran_locks
If multip...
Using group by on multiple columns
...one group.
To illustrate using an example, let's say we have the following table, to do with who is attending what subject at a university:
Table: Subject_Selection
+---------+----------+----------+
| Subject | Semester | Attendee |
+---------+----------+----------+
| ITB001 | 1 | John ...
Does MySQL index foreign key columns automatically?
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Yes, but only on innodb. Innodb is currently the only shipped table format that has foreign keys implemented.
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How do I create an HTML table with a fixed/frozen left column and a scrollable body?
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If you want a table where only the columns scroll horizontally, you can position: absolute the first column (and specify its width explicitly), and then wrap the entire table in an overflow-x: scroll block. Don't bother trying this in IE...