SQL CONVERT Function

In MySQL and SQL Server, the CONVERT function is very similar to the CAST function in that they both change the value from one data type to another. In this scenario, the syntax of the CONVERT function is as follows:

CONVERT (expression, [data type])

where [data type] is a valid data type in the RDBMS you are working with.

Let's go through an example to see how the CONVERT function is used. Let's assume we have the following table:

Table Student_Score

StudentID	integer
First_Name	char(20)
Score	float

and this table contains the following rows:

Table Student_Score

StudentID	First_Name	Score
1	Jenny	85.2
2	Bob	92.5
3	Alice	90
4	James	120.1

Example

SQL:

SELECT First_Name, CONVERT(Score, Integer) Int_Score FROM Student_Score

Result:

In Oracle, the CONVERT function is used differently. It converts a string from one character set to another. Its syntax is:

CONVERT (string, [new character set], [original character set])