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Effect of NOLOCK hint in SELECT statements
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1) Yes, a select with NOLOCK will complete faster than a normal select.
2) Yes, a select with NOLOCK will allow other queries against the effected table to complete faster than a normal select.
Why would this be?
NOLOCK typically (...
MySQL Query - Records between Today and Last 30 Days
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You need to apply DATE_FORMAT in the SELECT clause, not the WHERE clause:
SELECT DATE_FORMAT(create_date, '%m/%d/%Y')
FROM mytable
WHERE create_date BETWEEN CURDATE() - INTERVAL 30 DAY AND CURDATE()
Also note that CURDATE() returns only the DATE portion...
shortcut in Android Studio to locate the current editing src file
...l from Source (right click the empty area to the left of said button) now selects the opened file in the tree. Also, after enabling it, the button is removed.
– FirstOne
Nov 28 '17 at 12:28
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How to fix Error: “Could not find schema information for the attribute/element” by creating schema
...tudio, open your app.config or web.config file.
Go to the "XML" menu and select "Create Schema". This action should create a new file called "app.xsd" or "web.xsd".
Save that file to your disk.
Go back to your app.config or web.config and in the edit window, right click and select properties. From...
Error 1046 No database Selected, how to resolve?
...ation.
If you're trying to do this via MySQL Workbench...
...you need to select the appropriate database/catalog in the drop down menu found above the :Object Browser: tab. You can specify the default schema/database/catalog for the connection - click the "Manage Connections" options under the SQL...
How to specify a editor to open crontab file? “export EDITOR=vi” does not work
... 13.04 installation) try:
There are a number of alternative ways:
1) Run select-editor
select-editor
2) Manually edit the file: ~/.selected_editor specifying your preferred editor. With this option you can specify editor parameters.
# Generated by /usr/bin/select-editor
SELECTED_EDITOR="/usr/...
SQLite select where empty?
In SQLite, how can I select records where some_column is empty?
Empty counts as both NULL and "".
4 Answers
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How to get number of rows using SqlDataReader in C#
...reading all rows (and then you might as well store them)
run a specialized SELECT COUNT(*) query beforehand.
Going twice through the DataReader loop is really expensive, you would have to re-execute the query.
And (thanks to Pete OHanlon) the second option is only concurrency-safe when you use a ...
How to get a list of column names on Sqlite3 database?
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but you can't select from that table. It's just plain annoying. I'm trying something like this... but it don't work create temporary table TmpCols (cid integer, name text, type text, nn bit, dflt_value, pk bit); .mode insert TmpCols .out...
phpunit mock method multiple calls with different arguments
... ->with($this->logicalOr(
$this->equalTo('select * from roles'),
$this->equalTo('select * from users')
))
->will($this->returnCallback(array($this, 'myCallback')));
var_dump($mock->Query("select * from us...