Introduction:

This blog explores multiple methods to achieve the BLOB to TEXT conversion in MySQL, providing step-by-step explanations and accompanying code snippets. 

Method 1: Using the CAST() Function

To convert BLOB to TEXT in MySQL, you can use the CAST() function, which allows you to change the data type of a value. Here's how you can do it:

SELECT CAST(blob_column AS CHAR) AS text_column
FROM your_table;

In this method, the CAST() function is used to explicitly convert the blob_column from BLOB to CHAR (TEXT) data type. The result is presented as text_column. This method works well for small BLOBs that can be safely cast to TEXT.

Output:

+-------------+
| text_column |
+-------------+
| Hello World |
+-------------+

Method 2: Using the CONVERT() Function

Another approach is to use the CONVERT() function, which can be used to change data types and character sets:

SELECT CONVERT(blob_column USING utf8) AS text_column
FROM your_table;

In this method, the CONVERT() function is employed to convert the character set of blob_column to UTF-8 encoding, effectively transforming it into TEXT format. This method is particularly useful when dealing with character encoding issues.

Output:

+-------------+
| text_column |
+-------------+
| Hello World |
+-------------+

Method 3: Using the CONCAT() Function

The CONCAT() function can be used to concatenate BLOB data with an empty string, effectively converting it to TEXT:

SELECT CONCAT(blob_column, '') AS text_column
FROM your_table;

In this method, the CONCAT() function is utilized to combine the empty string with blob_column, resulting in the conversion of BLOB data to TEXT. This method can be helpful when dealing with larger BLOBs.

Output:

+-------------+
| text_column |
+-------------+
| Hello World |
+-------------+

Method 4: Using the HEX() and UNHEX() Functions

The HEX() and UNHEX() functions can be combined to convert BLOB to TEXT:

SELECT CONVERT(UNHEX(blob_column) USING utf8) AS text_column
FROM your_table;

In this method, the UNHEX() function is used to convert the BLOB data into its hexadecimal representation, which is then converted to TEXT using the CONVERT() function with UTF-8 encoding.

Output:

+-------------+
| text_column |
+-------------+
| Hello World |
+-------------+

Conclusion:

In this blog, we explored four different methods for achieving the BLOB to TEXT conversion in MySQL: using the CAST() function, the CONVERT() function, the CONCAT() function, and the combination of HEX() and UNHEX() functions.