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Is there any significant difference between using if/else and switch-case in C#?
... in debug or compatibility mode. In release, it will be compiled into jump table (through MSIL 'switch' statement)- which is O(1).
C# (unlike many other languages) also allows to switch on string constants - and this works a bit differently. It's obviously not practical to build jump tables for str...
What is cardinality in MySQL?
... of data values contained in a particular column (attribute) of a database table. The lower the cardinality, the more duplicated elements in a column. Thus, a column with the lowest possible cardinality would have the same value for every row. SQL databases use cardinality to help determine the opti...
How to fix “Incorrect string value” errors?
...ecting:
SET NAMES 'utf8';
SET CHARACTER SET utf8;
Next, verify that the tables where the data is stored have the utf8 character set:
SELECT
`tables`.`TABLE_NAME`,
`collations`.`character_set_name`
FROM
`information_schema`.`TABLES` AS `tables`,
`information_schema`.`COLLATION_CHARACTER_S...
jQuery .on function for future elements, as .live is deprecated [duplicate]
...tor for a static parent of the element. For example, if you have a static table element and tr elements are added dynamically to the DOM, you could do something like $('table#id').on('click', 'tr', ...)
http://api.jquery.com/live/
...
Fastest way to count exact number of rows in a very large table?
I have come across articles that state that SELECT COUNT(*) FROM TABLE_NAME will be slow when the table has lots of rows and lots of columns.
...
Datatables: Cannot read property 'mData' of undefined
I have an issue with Datatables . I also went through this link which didn't yield any results. I have included all the prerequisites where I'm parsing data directly into the DOM. Kindly help me to fix this issue.
...
Hide all but $(this) via :not in jQuery selector
...
$("table.tr").not(this).hide();
As an aside, I think you mean $("table tr") (with a space instead of a dot).
The way you have it, it selects every table which has a class of tr (eg, <table class="tr">), which is probab...
SQL JOIN - WHERE clause vs. ON clause
...r join has taken place.
b. ON clause - Before joining. Records (from right table) will be filtered before joining. This may end up as null in the result (since OUTER join).
Example: Consider the below tables:
1. documents:
| id | name |
--------|-------------|
| 1 ...
Why is a ConcurrentModificationException thrown and how to debug it
...
I agree however that if it is unpredictable, there is most likely a threading issue which is causing the conditions for this exception to occur. Which makes it all the more confusing because of the exception name.
– Robin
M...
How do I select an entire row which has the largest ID in the table?
...
You could use a subselect:
SELECT row
FROM table
WHERE id=(
SELECT max(id) FROM table
)
Note that if the value of max(id) is not unique, multiple rows are returned.
If you only want one such row, use @MichaelMior's answer,
SELECT row from table ORDER BY ...