PostgreSQL-Database/C2/Basic-SELECT-Statement/English
Title of the Script: Basic SELECT Statement
Author: EduPyramids
Keywords: postgreSQL, pgadmin 4, SELECT statement, asterisk operator, retrieve all the data, EduPyramids, Video Tutorial.
| Visual Cue | Narration |
| Slide 1
Title Slide |
Welcome to this Spoken Tutorial on Basic SELECT Statement. |
| Slide 2
Learning Objectives |
In this tutorial we will learn about,
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| Slide 3
System Requirement |
To record this tutorial, I am using
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| Slide 4
Prerequisite |
To follow this tutorial,
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| Slide 5
Code Files
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The following code file is required to practice this tutorial.
This file is provided in the Code Files link of this tutorial page. |
| Let us learn about the SELECT statement. | |
| Slide 6
SELECT statement |
The SELECT statement retrieves data from one or more tables in PostgreSQL.
It does not modify the data, but only displays the stored data. |
| Let’s get started. | |
| Show localhost server node | Please ensure that you are connected to the Localhost PostgreSQL server. |
| Select Studentdb | In the Browser pane, expand the Student db database. |
| Click students tableClick Columns node | Let us click on the students table.
Let us next click on the Columns node. |
| Slide 7
SELECT statement |
SELECT statement is used to select all columns or specific columns from a table.
Ensure that a table containing data already exists. |
| Slide 8 | Imagine a notebook with many student records.
How do we read the stored information easily? |
| Slide 9 | In databases, we use the SELECT statement to read data.
Pause and think of asking for details from a register. |
| Show the pgAdmin 4 records.Highlight Table. | Here, the table named students already exists.
This table stores student information. |
| Type: SELECT * FROM students; | Let us retrieve all the data from the table.
Type this command in the query window. |
| Highlight *(asterisk) | The asterisk symbol selects all the columns.
This command displays the entire data. |
| Click on the Execute query button. | Let us execute the query. |
| Highlight output: | Pause and observe the output carefully.Sometimes, we need only selected information. |
| Highlight: studentname column and dob column | Let us select studentname and d o b columns. |
| Type: SELECT studentname, dob FROM students;
Click the Execute query button. |
Now type the command.SELECT studentname, dob FROM students;
Lets Execute the query. |
| Highlight output. | Notice that only studentname and dob columns are displayed.
Other columns are not shown in the output. |
| Let us compare the results of both the queries. | |
| Split output view | The first query shows all columns from the table.
The second query shows only the selected columns. |
| Slide 10
Summary In this tutorial we have learnt about,
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With this we come to the end of this tutorial.
Let us summarise. |
| Slide 11
Assignment As an Assignment,
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As an assignment, please do the following. |
| Slide 12
Thank you |
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Thank you for joining. |