Summary
Zusammenfassung Vokabelliste PR3
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Ergänzung zur Skriptzusammenfassung Vokabelliste für die Inhalte
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Tabelle erzeugen CREATE TABLE <Tab> (<Spalte> Datentyp,…, PRIMARY KEY (<Spalte>));Tabelle/Spalte anzeigen SELECT */<Spalte> FROM <Tab>;
Werte hinzufügen INSERT INTO <Tab> (<Spalte>,…) VALUES (<Wert>,…);
Tupel löschen DELETE FROM <Tab> WHERE <Spalte>=<Wert>
Selektion (Abfragen aller Tupel, die eine (Reihe von ) Eigenschaf/en aufweisen) SELECT */<Spalte> FROM <Tab> WHERE <Suchbedingung> AND <Suchbedingung>…;
Primary Key PRIMARY KEY (<Spalte>,..)
Anordnung der Zeilen (DESC - absteigend; ASC - aufsteigend (voreingestellt)) SELECT <Spalten>,.. FROM <Tab> ORDER BY <Spaltenname o. nummer> DESC/ASC,...;
berechnete Werte SELECT <Spalte>,…,<Spalte n>*Wert AS NEUER_Spalte n FROM <Tab>;
Tabelle auswerten: zählen SELECT COUNT (*/<Spalte) FROM <Tab>;
Tabelle auswerten: summe SELECT SUM (*/<Spalte>) FROM <Tab>;
Abfragen Kreuzverbund (CROSS JOIN) SELECT * FROM <Tab>,<Tab2>; oder <Tab1> CROSS JOIN <Tab2>;
Abfrage Gleichheitsverbund (EQUI JOIN) (geht auch mit >,<, >=, <=) SELECT * FROM <Tab1>,<Tab2> WHERE <Spalte1>=<Spalte2 ; oder <Tab1> JOIN <Tab2> ON <Spalte1> = <Spalte1>;
Unterabfrage IN (in Klammer geschrieben: erstellt Tab mit Attribut N; IN: Werte aus anderer Tabelle mit gleichem Attribut N SELECT <Spalte1> FROM <Tab> WHERE <Spalte2> IN (SELECT <Spalte 2 FROM <Tab2> WHERE <Suchbedingung>;
Unterabfrage EXISTS SELECT <Spalte1> FROM <Tab1> WHERE EXISTS (SELECT <Spalte2> FROM <Tab2> WHERE <Suchbedingung>
Vereinigung der Tupelmengen (SELECT <Spalte1>,… FROM <TabA>) UNION (SELECT <Spalte1>,… FROM <TabB>)
Differenz der Tupelmengen (SELECT * FROM <TabA>) EXCEPT [ALL] CORRESPONDING BY (<Spalte>) (SELECT * FROM <TabB>;
Durchschnitt der Tupelmengen (SELECT * FROM <TabA>) INTERSECT [ALL] CORRESPONDING (SELECT * FROM <TabB>);
Integritätsbedingung Foreign- key FOREIGN KEY (<Spalte>,…) REFERENCES <tab>
Integritätsbedingung Check CHECK (<Suchbedingung>)
Trigger befehle hinzufügen CREATE TRIGGER
doppelte Werte streichen (z.B. nach SELECT) DISTINCT
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