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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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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).
...
MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
What is main difference between INSERT INTO table VALUES .. and INSERT INTO table SET ?
3 Answers
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Insert multiple rows WITHOUT repeating the “INSERT INTO …” part of the statement?
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INSERT INTO dbo.MyTable (ID, Name)
SELECT 123, 'Timmy'
UNION ALL
SELECT 124, 'Jonny'
UNION ALL
SELECT 125, 'Sally'
For SQL Server 2008, can do it in one VALUES clause exactly as per the statement in your question (you just need to add a comm...
How to check which locks are held on a table
...
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 ...
How to insert a row in an HTML table body in JavaScript
I have an HTML table with a header and a footer:
9 Answers
9
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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...
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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What is the difference between bottom-up and top-down?
...ds the root.
Tabulation - You can also think of dynamic programming as a "table-filling" algorithm (though usually multidimensional, this 'table' may have non-Euclidean geometry in very rare cases*). This is like memoization but more active, and involves one additional step: You must pick, ahead of...