Archive for July 2014

Almost Equal C#

Test if two values are almost equal.

/// Test if two doubles are approximately equal
/// Test variable one
/// Test variable two
/// epsilon a measure of equality
/// boolean true = values are approximately equal, false = values are not equal
public static Boolean almostEqual(double a, double b, double eps)
    return Math.Abs(a - b) < eps;

Example using the function.

double a = 1.234;
double b = 1.235;
double eps = 0.01;
Console.WriteLine("equal = " + almostEqual(a, b, eps).ToString());

Oracle Insert Date

A simple SQL example of using the To_Date function to format a date.


Backup Oracle database with Windows Batch Script

This simple batch script creates a new folder based on the date and time and then executes a oracle database dump.

REM Backup oracle database

@echo Starting database backup

REM get the current datestamp in the format year-month-day-hour-minute
SET DATESTAMP=%date:~6,4%-%date:~3,2%-%date:~0,2%-%time:~0,2%-%time:~3,2%

REM Create a new directory
md "c:\backup\%DATESTAMP%"

REM backup database
REM Dont forget to change username and password
exp username/password@xe FILE="c:\backup\%DATESTAMP%\databasename.dmp"

@echo Finished backing up database to c:\backup\%DATESTAMP%