Little endian and Big endian in oracle with example

 A big-endian system stores the most significant byte of a word at the smallest memory address and the least significant byte at the largest. A little-endian system, in contrast, stores the least significant byte at the smallest address.

Let's consider an example to demonstrate the concept of little endian and big endian in the context of an Oracle database. Imagine we have a table in an Oracle database that stores a 4-byte integer value. Let's call this table "ExampleTable" and the column "Value".

Little Endian:

In little-endian byte ordering, the least significant byte (LSB) is stored first, followed by the more significant bytes. So, if the integer value is 0x12345678, it would be stored in memory in the following byte order:

Address   |    Byte Value

------------------------

0x1000    |       0x78

0x1001    |       0x56

0x1002    |       0x34

0x1003    |       0x12

Big Endian:

In big-endian byte ordering, the most significant byte (MSB) is stored first, followed by the less significant bytes. So, if the integer value is 0x12345678, it would be stored in memory in the following byte order:

Address   |    Byte Value

------------------------

0x1000    |       0x12

0x1001    |       0x34

0x1002    |       0x56

0x1003    |       0x78

When working with Oracle, the byte order is typically determined by the underlying hardware architecture of the system. Oracle handles byte ordering transparently for most operations, so you don't usually need to worry about it explicitly.

However, if you need to handle byte ordering explicitly in your code, Oracle provides functions to convert between little endian and big endian byte orders. For example, you can use the TO_NUMBER function with the appropriate format model to convert a little-endian binary string to a number in Oracle.

Here's an example of converting a little-endian binary string to a number in Oracle:

SELECT TO_NUMBER('78563412', 'XXXXXXXX', 'NLS_NUMERIC_CHARACTERS=''.,''') AS ConvertedValue FROM DUAL;

In this example, '78563412' represents the little-endian binary string, and 'XXXXXXXX' is the format model specifying the byte order. The NLS_NUMERIC_CHARACTERS=''.,'' parameter ensures that the decimal separator is set correctly.

The result would be 2018915346, which is the decimal representation of the little-endian binary value 0x12345678.

Similarly, you can use other conversion functions like TO_CHAR or RAWTOHEX to convert values between little endian and big endian byte orders as needed.

Keep in mind that in most cases, you don't need to explicitly handle byte ordering when working with Oracle databases, as the database engine takes care of it automatically