Unterschiede
Hier werden die Unterschiede zwischen zwei Versionen angezeigt.
Nächste Überarbeitung | Vorhergehende Überarbeitung | ||
modul:m290:learningunits:lu07:theorie:03 [2024/09/30 10:48] – angelegt vdemir | modul:m290:learningunits:lu07:theorie:03 [2024/10/17 12:45] (aktuell) – vdemir | ||
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- | ====== | + | ====== |
+ | ** Sources: | ||
+ | - [[https:// | ||
+ | - [[https:// | ||
+ | - [[https:// | ||
- | ===== Learning Objectives | + | The UPDATE command is used to modify existing data in a table. It can be executed with or without a WHERE clause, depending on whether you want to update specific rows or all rows. |
- | ... | + | |
- | | + | ===== UPDATE with Filter (WHERE Clause) |
+ | Using a WHERE clause allows you to target specific rows to update. This ensures that only rows meeting a certain condition are modified. | ||
+ | |||
+ | **Syntax** | ||
+ | | ||
+ | SET column1 = value1, column2 = value2 | ||
+ | WHERE condition; | ||
+ | |||
+ | **Example** | ||
+ | UPDATE employees | ||
+ | SET salary = 60000 | ||
+ | WHERE employee_id = 1; | ||
+ | |||
+ | ===== UPDATE without Filter ===== | ||
+ | If you omit the WHERE clause, the UPDATE command will modify every row in the table, which can lead to unintended changes, so it must be used with caution. | ||
+ | |||
+ | **Syntax** | ||
+ | UPDATE table_name | ||
+ | SET column1 = value1; | ||
| | ||
+ | **Example** | ||
+ | UPDATE employees | ||
+ | SET salary = 70000; | ||
==== Vocabulary ==== | ==== Vocabulary ==== | ||
^English ^ Deutsch ^ | ^English ^ Deutsch ^ | ||
- | | Obsolete | + | | ...| ... | |
- | | result-set | Ergebnismenge | | + | |
---- | ---- | ||
[[https:// | [[https:// | ||