Cast and Convert Functions

Cast and convert functions transform data between different types.

Cast and convert functions include:

TO_DATE'(' value_returned_expression [, format_mask] ')' : Converts a string to a date using the specified format_mask.
Inputs: A string (VARCHAR2) and an optional format mask.
Example:
```
TO_DATE('2024-01-03','yyyy-MM-dd')
```
TO_TIMESTAMP'(' value_returned_expression [, format_mask] ')' : Converts a string to a timestamp using the specified format_mask.
Inputs: A string (VARCHAR2) and an optional format mask.
Example:
```
TO_TIMESTAMP('2024-01-03 01:01:01','yyyy-MM-dd HH:mm:ss')
```

CAST'(' value_returned_expression AS data_type ')' : Converts the expression to the specified data type.

Inputs: Any compatible data types.

Example:

CAST(CUSTOMERS.CUST_YEAR_OF_BIRTH AS VARCHAR2(20))

The following table shows the CAST compatibility between six datatypes: VARCHAR2, NUMBER, BIGDECIMAL, LARGEINT, DATE, and TIMESTAMP. The table cells indicate whether the CAST between the source and target datatypes is allowed (Yes) or not (No).

Source/Target	VARCHAR2	NUMBER	BIGDECIMAL	LARGEINT	DATE	TIMESTAMP
VARCHAR2	Yes	Yes	Yes	Yes	Yes	Yes
NUMBER	Yes	Yes	Yes	Yes	No	No
BIGDECIMAL	Yes	Yes	Yes	Yes	No	No
LARGEINT	Yes	Yes	Yes	Yes	No	No
DATE	Yes	No	No	No	Yes	Yes
TIMESTAMP	Yes	No	No	No	Yes	Yes

INT'(' value_returned_expression ')' : Converts an expression to an integer..
Inputs: Exact numeric types. Example: NUMBER, LARGEINT, DOUBLE, BIGDECIMAL.
Example:
```
INT('12.12') // function output will be 12
```
BIGINT'(' value_returned_expression ')' : Converts an expression to a large integer.
Inputs: Exact numeric types. Example: NUMBER, LARGEINT, DOUBLE, BIGDECIMAL.
Example:
```
BIGINT('1234567890.1234567890') // function output will be 1234567890
```