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Beide Seiten der vorigen Revision Vorhergehende Überarbeitung Nächste Überarbeitung | Vorhergehende Überarbeitung | ||
modul:m290:learningunits:lu07:theorie:04 [2024/09/30 13:12] – gelöscht vdemir | modul:m290:learningunits:lu07:theorie:04 [2024/10/17 13:49] (aktuell) – vdemir | ||
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+ | ====== LU08d - SQL-DML: DELETE ====== | ||
+ | |||
+ | **Sources: | ||
+ | * [[https:// | ||
+ | |||
+ | ===== 3. DELETE Statement ===== | ||
+ | The DELETE command is used to remove records from a table. Like UPDATE, it can be run with or without a filter, making it vital to define the condition to avoid unintended data removal. | ||
+ | |||
+ | ===== DELETE with Filter (WHERE Clause) ===== | ||
+ | Using a WHERE clause ensures that only specific rows matching the condition will be deleted. | ||
+ | |||
+ | **Syntax:** | ||
+ | DELETE FROM table_name | ||
+ | WHERE condition; | ||
+ | |||
+ | **Example** | ||
+ | DELETE FROM employees | ||
+ | WHERE employee_id = 1; | ||
+ | | ||
+ | | ||
+ | ===== DELETE without Filter ===== | ||
+ | Omitting the WHERE clause removes all data from the table, so it must be used cautiously. This operation doesn’t remove the table structure, just the rows. | ||
+ | |||
+ | **Syntax:** | ||
+ | DELETE FROM table_name; | ||
+ | |||
+ | **Example: | ||
+ | DELETE FROM employees; | ||
+ | |||
+ | |||
+ | |||
+ | ==== Vocabulary ==== | ||
+ | ^English ^ Deutsch ^ | ||
+ | | ...| ... | | ||
+ | |||
+ | ---- | ||
+ | [[https:// | ||