PL/SQL Programing -4 Characters and Data types

Hello, PL / SQL Programming articles continue. In my previous article, we talked about function, procedure blocks, and today we will look at character sets and data types. I recommend that you read the previous article before proceeding with this article.

PLSQL Programing -3


Predefined Data Types:

This part can be a bit boring data types will be examined briefly.

Numeric: Contains numerical values used in arithmetic operations.

Character: The data type that holds a character

Boolean: Holds either True or False

Datetime: Data type with date and time

Number: This is the area where the numeric data is kept. NUMBER (full decimal).


PLS_INTEGER – BINARY_INTEGER: Unlike Number type, it performs faster arithmetic operations and takes less space.

BINARY_FLOAT – BINARY_DOUBLE: The data type ends with f (5.67f) and ends with d in BINARY_DOUBLE.

VARCHAR2 – NVARCHAR2: Variable is the field in which the alphanumeric or byte data is held.

TIMESTAMP: Keeps data of year, day, month, hour, minute and second.

test1 VARCHAR2(10):='Oracle';
test2 VARCHAR2(10):='Oracle ';
IF test1=test2 THEN
DBMS_OUTPUT.PUT_LINE(test1 ||'ile' ||test2||'aynıdır');
DBMS_OUTPUT.PUT_LINE(test1||' ile '||test2||'aynı değildir');


In the example, put a space character at the end of the test 2 variables and do a test.



LOB (Large Object) Data Types:

Data types are data types that hold data that are not of a particular data type (image, image, etc.).

BFILE: Large binary objects that are held outside the database on the operating system. It cannot exceed 4GB.

BLOB: These are large binary objects that are kept in the database and are 8 to 12TB in size.

CLOB: Character data is in large blogs is 8 to 12TB size.

NCLOB: NLS holds Unicode data of character type. It is 8 to 12TB in size.



I mentioned the variables part in PL / SQL Programming-1 article and finally I wanted to explain CONSTANT and DEFAULT usage.

We use it whenever we want to assign a constant value to the CONSTANT variable, which is similar to the static keyword in programming languages.

DEAULT: When defining the variable, we can give an unstable and variable value.


In the next article, we will continue with IF-ELSE structures.

About Deniz Parlak

Hi, i’m Security Data Scientist & Data Engineer at My Security Analytics. I have experienced Advance Python, Machine Learning and Big Data tools. Also i worked Oracle Database Administration, Migration and upgrade projects. For your questions [email protected]

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