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WITH (NOLOCK) vs SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
...se the set transaction isolation level statement, it will apply to all the tables in the connection, so if you only want a nolock on one or two tables use that; otherwise use the other.
Both will give you dirty reads. If you are okay with that, then use them. If you can't have dirty reads, then co...
How to compare dates in datetime fields in Postgresql?
...tween dates in postgresql(version 9.2.4 in windows). I have a column in my table say update_date with type 'timestamp without timezone'. Client can search over this field with only date (i.e: 2013-05-03) or date with time (i.e: 2013-05-03 12:20:00). This column has the value as timestamp for all row...
PHP PDO returning single row
...-- connection string --- ");
$stmt = $dbh->prepare("SELECT name FROM mytable WHERE id=4 LIMIT 1");
$stmt->execute();
$row = $stmt->fetch();
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NoSQL Use Case Scenarios or WHEN to use NoSQL [closed]
...L DBs often lack the ability to perform atomic operations across multiple "tables".
You really need to look at and understand what the various types of NoSQL stores are, and how they go about providing scalability/data security etc. It's difficult to give an across-the-board answer as they really ...
How to vertically align into the center of the content of a div with defined width/height?
...I have found you have four options:
Version 1: Parent div with display as table-cell
If you do not mind using the display:table-cell on your parent div, you can use of the following options:
.area{
height: 100px;
width: 100px;
background: red;
margin:10px;
text-align: center;
...
Oracle SQL Query for listing all Schemas in a DB
...le mean it's a user ? I mean a schema = user ? and under that user all the tables created same like MySQL ?
– Osama Al-Banna
Jun 15 '16 at 14:12
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Ruby on Rails - Import Data from a CSV file
I would like to import data from a CSV file into an existing database table. I do not want to save the CSV file, just take the data from it and put it into the existing table. I am using Ruby 1.9.2 and Rails 3.
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How to do a regular expression replace in MySQL?
I have a table with ~500k rows; varchar(255) UTF8 column filename contains a file name;
13 Answers
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How to use GROUP BY to concatenate strings in MySQL?
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SELECT id, GROUP_CONCAT(name SEPARATOR ' ') FROM table GROUP BY id;
http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
From the link above, GROUP_CONCAT: This function returns a string result with the concatenated non-NULL values from a ...
What is the significance of load factor in HashMap?
...apacity and load factor. The capacity is the number of buckets in the hash table, and the initial capacity is simply the capacity at the time the hash table is created. The load factor is a measure of how full the hash table is allowed to get before its capacity is automatically increased. When the ...