94 lines
2.5 KiB
Markdown
94 lines
2.5 KiB
Markdown
---
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title: SQL Drop View Statement
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---
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## SQL Drop View Statement
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### Introduction
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This guide covers the SQL statement for dropping (deleting) one or more view objects.
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A View is an object that presents data from one or more tables.
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Note: before deleting or changing data or objects, remember to have a fresh backup.
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We will cover:
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* Using SQL to drop a table
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* Using the workbench to drop a view
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We'll be using MySQL for the demontration. Check the manual for this function in other Database Managers.
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we'll use student table in this tutorial.
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```sql
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select studentID,FullName,sat_score from student;
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```
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Result :
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```text
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+------------+---------------------+-----------+
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| studentID | FullName | sat_score |
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+------------+---------------------+-----------+
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| 1 | Vincent Uvalle | 400 |
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| 2 | Merle Veres | 800 |
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| 3 | Donte Emmons | 1000 |
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| 4 | Demetrius Mccaster | 1200 |
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| 5 | Tim Goudy | 1400 |
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| 6 | Stephan Monfort | 1600 |
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| 7 | Maximo Backstrom | 1800 |
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| 8 | Dean Pickel | 200 |
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+------------+---------------------+-----------+
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```
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First of all let's create a view.
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```sql
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create view [Failures] AS
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select studentID, FullName , sat_score
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from student
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where sat_score <= 400;
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```
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Let's see what Failures view consists of
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```sql
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select * from [Failures]
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```
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Result :
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```text
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+------------+---------------------+-----------+
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| studentID | FullName | sat_score |
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+------------+---------------------+-----------+
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| 1 | Vincent Uvalle | 400 |
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| 8 | Dean Pickel | 200 |
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+------------+---------------------+-----------+
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```
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### Basic Syntax
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```sql
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drop view [IF EXISTS]
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view_name [, view_name] ...
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```
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### Drop View SQL
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The if exists portion will "trap" errors, should the view not exist.
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```sql
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drop view if exists [Failures];
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```
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Result :
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```text
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Failures table dropped successfully.
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```
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### Using the Workbench
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From the workbench:
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1) Right click on the view to drop
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2) select drop view from the menu
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3) Select either either a) run SQL to review the SQL statement to be executed or b) drop new
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*As with all of these SQL things there is MUCH MORE to them than what's in this introductory guide. I hope this at least gives you enough to get started.
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Please see the manual for your database manager and have fun trying different options yourself.*
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