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How to create a table in SQL | SQL tutorial for beginners |SQL create table

How to create a table in SQL

In this tutorial, we will learn how to create a table in SQL. For creating a new oracle table we will use CREATE TABLE statement in the oracle database. It must be noted that we should have privilege to CREATE TABLE in sql schema. Also the sql table should have quota for table space.

SYNTAX for CREATE TABLE

CREATE TABLE schema_name.table_name (
    column_1 data_type column_constraint,
    column_2 data_type column_constraint,
    ...
    ...
 );

In the above SQL code we can see

CREATE TABLE : It is the main clause under which other information is put.
schema_name.table_name : We will mention schema name and then table name which we wanted to create. There are some

SQL data types for Oracle/PLSQL

PLSQL datatypes

In this article, we will understand briefly PLSQL datatypes. Each value in PL/SQL such as constant, variable, or parameter has a data type that defines their storage and calculation behavior. PL/SQL has basically two types of data types e.g scalar and composite.

Types of sql data types

Scalar data types

In scalar data type are those data type that stores a single value. Scalar data type has further four data subtypes

Number
Boolean
Character
Datetime

Composite data types

Whereas composite data type stores multiple values. There are two data sub types of composite data types are available.

Record
Collection

In this article, we will be discussing only scalar data type

Oracle number data type

The numeric data … Continue Reading

Oracle dual table: what is dual table in oracle

Oracle dual table

Oracle dual table is a table automatically created by oracle database along with the data dictionary. DUAL is in the schema of the user SYS but is accessible by the name DUAL to all users.

Why dual oracle table is required

In oracle, SELECT statement requires FROM clause, which fetches data from oracle table. But in some scenarios, we have constant values which is not available in any table and we need to refer to these values in our SQL queries as additional value. To use these we require SQL DUAL table.

select lower('I AM AN ANALYST') from dual;

In the above example, we wanted to use a constant value ‘I AM AN ANALYST’ in a small … Continue Reading

Oracle SQL developer download : How to install oracle sql developer

SQL developer download

In this article we will be learning sql developer download for windows 10. Oracle sql developer installation is very easy and I will be explaining it in step by step method. We will also be learning how to create connection in SQL developer with SQL database which we learned in our previous article.

how to install oracle sql developer

To install SQL developer we will first go this link the download on Windows 64-bit with JDK 8 included if we don’t have java installed on our system else we can download Windows 32-bit/64-bit.

We click on the download icon it will redirect to other page for Sign In. If you already have … Continue Reading

How to install Oracle database: Easy steps to install Oracle database in windows

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How to install Oracle database

Types of Oracle database

Oracle is providing three types of databases to download.

Enterprise Edition – It is a common and expensive edition of oracle database. There is no limit on memory or database size, and it provides many features that are not available to other editions.
Standard Edition – It is a limited edition of enterprise edition, and it also has no limit on memory or database limit. It also provides many features but less than oracle enterprise edition.
Expression Edition – It is a free-to-use version of oracle database and has very limited features. Like it uses a maximum of 2GB of RAM and has 12GB of user data.

A Step By Step

How to Install Anaconda for Windows

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How to Install Anaconda for Windows

Are you a data geek? Want to know how to install Anaconda for windows. Also want to write your first python or R code with the best distribution platform which arranges code for both.

So I am here with this blog, we will learn about the complete Anaconda setup method (Download and Install Anaconda Python) for Windows.

What Is Anaconda?

Anaconda is a tool that is used in Machine Learning and Data Science. It is a free open source distribution for R and Python Programming Language. It contains the source of software for heavy data processing, data analytics, and many more.

In the below blog, I will be guiding you step-by-step through downloading as … Continue Reading

How to create multiple worksheets from a list of cell values using VBA

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How to create multiple worksheets from a list

In our earlier article, we learned about how to create multiple worksheets in excel without using VBA. In this article, we will be learning How to create multiple worksheets from a list of cell values using VBA.

First, we will create a list of names that we wanted to name the worksheets.

How to create multiple worksheets from a list of cell values using VBA

After making the list we will select the range as our VBA code will work on the selection method.

Sub AddWorksheetsFromSelection()
Dim Ws As Worksheet
Dim Sr As Range
Dim c As Range

Sub AddWorksheetsFromSelection()
    Dim Ws As Worksheet
    Dim Sr As Range
    Dim c

How to create multiple worksheets from a list of cell values without VBA

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Creating Worksheets from a List of Names

Creating multiple worksheets from a list of values is very easy and it could be created by multiple methods. In this article, we will explore ways of creating it by using the following method. Though manually creating worksheets will be very time-consuming and using some tricks could make easy the task.

The first step in creating the task is to list all the values that we wanted to name the worksheets.

After listing the name insert a pivot table by using the newly created list as data range. After inserting the pivot table put the name of worksheet column in pivot table Filter as illustrated in the … Continue Reading

How to create a dynamic table in excel to summarize data

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Creating a dynamic table in excel

In this example, we will be creating a dynamic table in excel from a dataset. The dataset has 3 columns out of these three 2 are categorical values while the third is numerical. Now we wanted to create a dynamic table that will have these two columns as rows and columns. Also, we wanted to summarise our data by as count of entries of these two categorical columns. Dataset is illustrated in the below image.

To create this kind of excel dynamic table we will first convert our dataset into the excel table. You must be wondering why we are converting this into the table, this is because … Continue Reading

Difference between Primary Key and Foreign Key

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Difference between Primary Key and Foreign Key

A primary key is used to ensure data in the specific column is unique. It is a column that cannot have NULL values. It is either an existing table column or a column that is specifically generated by the SQL database according to a defined sequence.

What is Primary key:

Example: Refer to the image above:
STUD_NO, as well as STUD_PHONE both, are candidate keys for relation STUDENT but STUD_NO can be chosen as the primary key (only one out of many candidate keys).

What is a Foriegn key:

Example: Refer to the above image
STUD_NO in STUDENT_COURSE is a foreign key to STUD_NO in … Continue Reading