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SQL Server NOLOCK and joins
...argument, just your original question.
Yes, you need WITH(NOLOCK) on each table of the join. No, your queries are not the same.
Try this exercise. Begin a transaction and insert a row into table1 and table2. Don't commit or rollback the transaction yet. At this point your first query will retu...
Simplest way to do a recursive self-join?
...is the simplest way of doing a recursive self-join in SQL Server? I have a table like this:
5 Answers
...
Import CSV to SQLite
I'm trying to import a csv file to an SQLite table.
10 Answers
10
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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).
...
Real life example, when to use OUTER / CROSS APPLY in SQL
...ORDER BY pr.name) pa
ORDER BY pr.name,
pa.name
2) Calling a Table Valued Function for each row in the outer query
SELECT *
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle)
3) Reusing a column alias
SELECT number,
doubled_number,
...
When to use “ON UPDATE CASCADE”
... ON UPDATE CASCADE would allow you to change the primary key value and any tables that have foreign key references to the value will be changed accordingly.
In reference to #4, if you change the child ID to something that doesn't exist in the parent table (and you have referential integrity), you s...
MySQL Fire Trigger for both Insert and Update
...ossible to fire a mysql trigger for both the insert and update events of a table?
3 Answers
...
PostgreSQL - how to quickly drop a user with existing privileges
...
Doing: CREATE TABLE foo(bar SERIAL); ALTER TABLE foo OWNER TO postgres; CREATE USER testuser; GRANT ALL ON foo TO testuser; DROP USER testuser gave the error messages: ERROR: role "testuser" cannot be dropped because some objects depend...
In a bootstrap responsive page how to center a div
...http://getbootstrap.com/dist/css/bootstrap.css');
html, body, .container-table {
height: 100%;
}
.container-table {
display: table;
}
.vertical-center-row {
display: table-cell;
vertical-align: middle;
}
<script src="http://cdnjs.cloudflare.com/ajax/libs/twitter-bootst...
Is the primary key automatically indexed in MySQL?
...m/doc/refman/5.5/en/optimizing-primary-keys.html
The primary key for a table represents the column or set of columns
that you use in your most vital queries. It has an associated index,
for fast query performance
For MySQL 5.0 reference see: http://dev.mysql.com/doc/refman/5.0/en/mysql-ind...