modul:m290:learningunits:lu05:theorie:02

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modul:m290:learningunits:lu05:theorie:02 [2024/09/25 16:11] – vdemirmodul:m290:learningunits:lu05:theorie:02 [2024/10/17 12:43] (aktuell) – vdemir
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-====== LU06b - SQL-DDL: Table Management ======+====== LU07b - SQL-DDL: Table Management ======
  
 **Source**:  **Source**: 
-  * [[https://www.w3schools.com/sql/sql_create_table.asp|CREATE TABLE]] +  * [[https://www.w3schools.com/sql/sql_create_table.asp| W3Schools | CREATE TABLE]] 
-  * [[https://www.w3schools.com/sql/sql_alter.asp|ALTER TABLE]] +  * [[https://www.w3schools.com/sql/sql_alter.asp| W3Schools | ALTER TABLE]] 
-  * [[https://www.w3schools.com/sql/sql_drop_table.asp|DROP TABLE]]+  * [[https://www.w3schools.com/sql/sql_drop_table.asp| W3Schools | DROP TABLE]]
    
 ===== Learning Objectives ===== ===== Learning Objectives =====
 In this learning unit, we will learn how to manage database tables, i.e.  In this learning unit, we will learn how to manage database tables, i.e. 
-  -how to create +  - how to create 
-  -how to modify and  +  - how to modify and  
-  -how to delete database tables. +  - how to delete database tables
  
 ===== CREATE TABLE ===== ===== CREATE TABLE =====
 Let's start by creating a table based on the ERD of the student management tool, as shown below: Let's start by creating a table based on the ERD of the student management tool, as shown below:
  
-Our goal is to create the table "stundent" on our database. For that we need to know how the basic syntax for creating table is.+Our goal is to create the table "stundent" in our database. For that we need to know how the basic syntax for creating of table is.
  
   CREATE TABLE table_name (   CREATE TABLE table_name (
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 In our example the our concrete CREATE statement would look like: In our example the our concrete CREATE statement would look like:
 +''
   CREATE TABLE student (   CREATE TABLE student (
     stundent_id INT,     stundent_id INT,
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   ALTER COLUMN column_name datatype;   ALTER COLUMN column_name datatype;
      
-And of course, as a concrete practical example, in which we change the length of the column name from 50 characters to 100:+And of course, as a concrete practical example, in which we change the length of the column "name" from 50 characters to 100:
    
   ALTER TABLE student   ALTER TABLE student
   MODIFY COLUMN name VARCHAR(100);   MODIFY COLUMN name VARCHAR(100);
 +  
 +===== DROP TABLE =====
 +If, for whatever reason, we have created a table incorrectly or want to get rid of an obsolete table, we need the command DROP TABLE:
 +
 +  DROP TABLE table_name;
 +
 +**Hint: <color #ed1c24>Be careful with this command, as it also deletes the entire contents of this table.</color>**
  
 ==== Vocabulary ==== ==== Vocabulary ====
 ^English ^ Deutsch ^ ^English ^ Deutsch ^
-| ::: | ... |+| column | Spalte |
  
 ---- ----
 [[https://creativecommons.org/licenses/by-nc-sa/4.0/|{{https://i.creativecommons.org/l/by-nc-sa/4.0/88x31.png}}]] Volkan Demir [[https://creativecommons.org/licenses/by-nc-sa/4.0/|{{https://i.creativecommons.org/l/by-nc-sa/4.0/88x31.png}}]] Volkan Demir
  
  • modul/m290/learningunits/lu05/theorie/02.1727273460.txt.gz
  • Zuletzt geändert: 2024/09/25 16:11
  • von vdemir