Data types and variables in PLSQL with example

PL/SQL has a rich set of data types for variables and constants. These data types can be broadly categorized into three groups:

1. Scalar data types: These are basic data types that can hold a single value. Examples of scalar data types in PL/SQL include NUMBER, VARCHAR2, DATE, and BOOLEAN.
2. Composite data types: These data types can hold multiple values of different data types. Examples of composite data types in PL/SQL include records, tables, and objects.
3. LOB data types: These data types can hold large amounts of data, such as images, audio, and video. Examples of LOB data types in PL/SQL include BLOB, CLOB, and NCLOB.

In PL/SQL, variables are used to store values that can be used and manipulated within the code. Variables can be declared using the keyword “VARIABLE” followed by the variable name, and the data type. For example:

You can also initialize the variables when you declare them like this:

PL/SQL also supports the use of constants, which are fixed values that cannot be changed once they are assigned. Constants are declared using the keyword “CONSTANT” followed by the constant name, the data type, and the value. For example:

Overall, PL/SQL provides a wide range of data types and variables that can be used to store and manipulate data within the code, providing developers with the flexibility to create robust and efficient database applications.

here are a few examples of how to use different data types and variables in PL/SQL:

• Using the NUMBER data type:

• Using the VARCHAR2 data type:

• Using the DATE data type:

• Using the BOOLEAN data type:

• Using a composite data type, RECORD:

• Using a constant:

These are just a few examples, but PL/SQL offers many other data types and variables, each with its own unique properties and uses.