Unterschiede
Hier werden die Unterschiede zwischen zwei Versionen angezeigt.
| Beide Seiten der vorigen Revision Vorhergehende Überarbeitung Nächste Überarbeitung | Vorhergehende Überarbeitung | ||
| modul:m290:learningunits:lu05:theorie:01 [2024/10/24 12:46] – vdemir | modul:m290:learningunits:lu05:theorie:01 [2024/10/24 12:50] (aktuell) – vdemir | ||
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| Zeile 8: | Zeile 8: | ||
| - How to connect to one specific db-instance. | - How to connect to one specific db-instance. | ||
| - how you can delete obsolete or no longer required databases. | - how you can delete obsolete or no longer required databases. | ||
| - | |||
| - | ===== Access to the db with Webstorm code editor ===== | ||
| - | There are many ways how we can connect to our database instance. One way is from the terminal or commandline. Instead, during the module 290 we are going to use do the management with the code editor WEBSTORM, which is pictured below. | ||
| - | |||
| - | - New connection to our MySQL database system | ||
| - | - The already existing connections to our database instance | ||
| - | - New terminal window to the database to enter sql commands (leads to 4.) | ||
| - | - Terminal to the database to enter our SQL commands | ||
| - | - Execute button that sends the SQL command to the database | ||
| - | |||
| - | {{: | ||
| ===== DB Schema vs. DB Instance ===== | ===== DB Schema vs. DB Instance ===== | ||
| A database schema and a database instance are related concepts in the context of a database system, but they refer to different aspects: | A database schema and a database instance are related concepts in the context of a database system, but they refer to different aspects: | ||
| - | **1. Database Schema:** | + | {{: |
| + | |||
| + | ==== 1. Database Schema | ||
| The schema is the structure or blueprint that defines how data is organized within the database. It describes the database' | The schema is the structure or blueprint that defines how data is organized within the database. It describes the database' | ||
| Zeile 34: | Zeile 25: | ||
| Think of the schema as the blueprint or structure of the database that remains mostly static or changes rarely. | Think of the schema as the blueprint or structure of the database that remains mostly static or changes rarely. | ||
| - | **2. Database Instance:** | + | ==== 2. Database Instance: |
| The instance refers to the actual data stored in the database at a particular point in time. It is the current state of the database, including all of the records or entries inside the tables defined by the schema. | The instance refers to the actual data stored in the database at a particular point in time. It is the current state of the database, including all of the records or entries inside the tables defined by the schema. | ||
| - | It includes actual rows of data in the tables. | + | * It includes actual rows of data in the tables. |
| - | The instance can change frequently as data is inserted, updated, or deleted. | + | |
| - | You can think of the instance as the current snapshot of the database contents, while the schema defines the permanent framework. | + | |
| - | Analogy: | + | ==== Analogy |
| The schema is like the blueprint of a building (defining rooms, walls, and layout), while the instance is like the current state of the building (furniture, people inside, and their positions, which can change). | The schema is like the blueprint of a building (defining rooms, walls, and layout), while the instance is like the current state of the building (furniture, people inside, and their positions, which can change). | ||
| + | |||
| + | ===== Access to the db with Webstorm code editor ===== | ||
| + | There are many ways how we can connect to our database instance. One way is from the terminal or commandline. Instead, during the module 290 we are going to use do the management with the code editor WEBSTORM, which is pictured below. | ||
| + | |||
| + | - New connection to our MySQL database system | ||
| + | - The already existing connections to our database instance | ||
| + | - New terminal window to the database to enter sql commands (leads to 4.) | ||
| + | - Terminal to the database to enter our SQL commands | ||
| + | - Execute button that sends the SQL command to the database | ||
| + | |||
| + | {{: | ||
| ===== Commands ===== | ===== Commands ===== | ||