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What makes a SQL statement sargable?
...non-sargable is to include a field inside a function in the where clause:
SELECT ... FROM ...
WHERE Year(myDate) = 2008
The SQL optimizer can't use an index on myDate, even if one exists. It will literally have to evaluate this function for every row of the table. Much better to use:
WHERE myDat...
Save PL/pgSQL output from PostgreSQL to a CSV file
...e or automate, you can use Postgresql's built in COPY command. e.g.
Copy (Select * From foo) To '/tmp/test.csv' With CSV DELIMITER ',' HEADER;
This approach runs entirely on the remote server - it can't write to your local PC. It also needs to be run as a Postgres "superuser" (normally called "ro...
Encrypt Password in Configuration Files? [closed]
...nt keyLength = 128;
SecretKeySpec key = createSecretKey(password.toCharArray(),
salt, iterationCount, keyLength);
String originalPassword = "secret";
System.out.println("Original password: " + originalPassword);
String encryptedPassword = encrypt(orig...
Is it possible to use Java 8 for Android development?
...ce
Click on the Android SDK Manager button which is located on the toolbar
Select Android SDK Build tools Rev. 19.1 and Android Support Library only. Un-select everything else and install these two packages.
If everything goes well, ADT will be up and running.
The installation of the following to...
Get the last inserted row ID (with SQL statement) [duplicate]
...alue using:
INSERT INTO dbo.YourTable(columns....)
VALUES(..........)
SELECT SCOPE_IDENTITY()
This works as long as you haven't inserted another row - it just returns the last IDENTITY value handed out in this scope here.
There are at least two more options - @@IDENTITY and IDENT_CURRENT - r...
Convert Unix timestamp into human readable date using MySQL
...
Use FROM_UNIXTIME():
SELECT
FROM_UNIXTIME(timestamp)
FROM
your_table;
See also: MySQL documentation on FROM_UNIXTIME().
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symbol(s) not found for architecture i386
....
To add frameworks, right click on the project name in the project view, select Add, then select Existing frameworks... from the list. Then find the framework with the symbols you're missing.
As to how you find which frameworks you need, I've found using google the easiest, though you could proba...
Java: Subpackage visibility?
...rotected byte[] getDataAsBytes(){ return data.getBytes(); }
protected char[] getDataAsChars(){ return data.toCharArray(); }
}
make a class in that package that overrides the methods you need in ClassInA:
package a.b;
import a.ClassInA;
public class ClassInAInB extends ClassInA{
ClassIn...
LINQ query on a DataTable
...w in myDataTable.AsEnumerable()
where myRow.Field<int>("RowNo") == 1
select myRow;
And as @Keith says, you'll need to add a reference to System.Data.DataSetExtensions
AsEnumerable() returns IEnumerable<DataRow>. If you need to convert IEnumerable<DataRow> to a DataTable, use the...
Regex (grep) for multi-line search needed [duplicate]
I'm running a grep to find any *.sql file that has the word select followed by the word customerName followed by the word from . This select statement can span many lines and can contain tabs and newlines.
...