PostgreSQL BIT_LENGTH() function

BIT_LENGTH() function

The PostgreSQL bit_length function is used to count the number of bits in a specified string. It is a built-in function, is particularly useful when you need to determine the bit length of string data, which can be important for storage, transmission, and encryption purposes.

Uses of BIT_LENGTH() Function

• Storage Analysis: Helps in determining the storage requirements for string data in bits.


• Data Transmission: Useful in scenarios where data needs to be transmitted in bit-form.


• Encryption: Assists in encryption algorithms that operate on bit-level data.


• Data Compression: Useful for analyzing the bit-length to understand potential compression ratios.


• Validation: Ensures the integrity of data by validating the bit length of strings.

Syntax:

 bit_length (str1)
 

Parameters:

PostgreSQL Version

• Compatible with PostgreSQL version 9.3 and later.

Visual Presentation of PostgreSQL BIT_LENGTH() function

Example: PostgreSQL BIT_LENGTH() function

The following PostgreSQL statement will return the length of the given string 'w3resource'' in bits, i.e. 80.

Code:

SELECT bit_length('w3resource') AS "bit_length";

Sample Output:

 bit_length
------------
         80
(1 row)

Example: Empty String

The following PostgreSQL statement will return the length of the given empty string.

Code:

SELECT bit_length('') AS "bit_length";

Sample Output:

bit_length|
----------+
         0|
(1 row)

Example: String with Spaces

Code:

SELECT bit_length('w3 resource') AS "bit_length";

Sample Output:

bit_length|
----------+
        88|

Example: Multibyte Character String

Code:

SELECT bit_length('こんにちは') AS "bit_length";

Sample Output:

bit_length|
----------+
       120|

Example: Using with TEXT Type Data Type

Code:

SELECT bit_length(CAST('hello' AS TEXT)) AS "bit_length";

Sample Output:

bit_length|
----------+
        40|

Example: Using with CHAR Type Data Type

Code:

SELECT bit_length(CAST('hello' AS CHAR(10))) AS "bit_length";

Sample Output:

bit_length|
----------+
        40|

Example: Using with VARCHAR Type Data Type

Code:

SELECT bit_length(CAST('hello' AS VARCHAR(10))) AS "bit_length";

Sample Output:

bit_length|
----------+
        40|

Example: Using with CONCAT() Function

Code:

SELECT bit_length(CONCAT('hello', 'world')) AS "bit_length";

Sample Output:

bit_length|
----------+
        80|

Example: Using with SUBSTRING() Function

Code:

SELECT bit_length(SUBSTRING('hello world' FROM 1 FOR 5)) AS "bit_length";

Sample Output:

bit_length|
----------+
        40|

Example: Using with TRIM() Function

Code:

SELECT bit_length(TRIM('  hello  ')) AS "bit_length";

Sample Output:

bit_length|
----------+
        40|

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