Relational Data Bases
🇬🇧
In Inglés
In Inglés
Practique preguntas conocidas
Manténgase al día con sus preguntas pendientes
Completa 5 preguntas para habilitar la práctica
Exámenes
Examen: pon a prueba tus habilidades
Pon a prueba tus habilidades en el modo de examen
Aprenda nuevas preguntas
Popular en este curso
Aprende con fichas
Modos dinámicos
InteligenteMezcla inteligente de todos los modos
PersonalizadoUtilice la configuración para ponderar los modos dinámicos
Modo manual [beta]
Seleccione sus propios tipos de preguntas y respuestas
Otros modos disponibles
Completa la oración
Escuchar y deletrearOrtografía: escribe lo que escuchas
elección múltipleModo de elección múltiple
Expresión oralResponde con voz
Expresión oral y comprensión auditivaPractica la pronunciación
EscrituraModo de solo escritura
Relational Data Bases - Marcador
También te puede interesar
Relational Data Bases - Detalles
Niveles:
Preguntas:
25 preguntas
| 🇬🇧 | 🇬🇧 |
| Table Joins | Cross Inner / Natural Outer( Left Right Full) |
| Table Joins | Cross Inner / Natural Outer( Left Right Full) |
| Table Joins | Cross Inner / Natural Outer( Left Right Full) |
| Entity Type | Thing about which data is kept |
| ATTRIBUTE | Property of entity |
| INSTANCE | An occurrence of an entity type |
| IDENTIFIER | Attribute that uniquely identifies an instance |
| • TABLE/RELATION | Representation of an entity |
| FIELD/COLUMN | Representation of an attribute |
| RECORD/ROW | Represents an instance |
| KEY | Represents an identifier |
| Relationship | Joins tables |
| Field value | Assigned to a field |
| Data type | Kind of data stored in field |
| Foreign key – | Key from one table added to second table to create relationship |
| Database | An organized collection of data |
| Database Management Systems (DBMS) I | A software system that stores, manages, and facilitates access to one or more databases. E.g. Oracle, MS Access, SQL Server, SQLite, mySQL PostgreSQL |
| Schema | Collection of objects in a database e.g. tables, views, indexes |
| JOIN | To select data from more than one table vvvv |
| Benefits of Relational Data Base | Reduces data duplication ,Improves integrity ,Facilitates querying Facilitates access contro |
| Create database | CREATE DATABASE dbasename CREATE TABLE tablename ( Col1 type col2 type … ); *Constraints may be added to columns e.g. PRIMARY KEY, CHECK, FOREIGN KE |
| Drop Database | DROP DATABASE dbasename; DROP TABLE tablename; |
| Alter | ALTER TABLE tablename ADD col type; DROP COLUMN colname ; MODIFY COLUMN colname type; |
| Insert into | INSERT INTO tablename (col1, col2, col3, …) VALUES (v1, v2, V3, …), (v1, v2, v3, …), (V1, V2, V3, …), …; |
| Database update | UPDATE tablename SET col = value WHERE rowfilter; *Note the omitting the WHERE clause will cause all rows to be updated |
| Select | SELECT col1, col2, col3, expr1, … FROM tablename WHERE rowfilter ORDER BY column LIMIT count OFFSET offset GROUP BY column HAViNG groupfilter; -SELECT * to select all columns WHERE, ORDER BY, LIMIT, GROUP BY, HAVING are all optional clauses |
| Delete | DELETE FROM tablename WHERE rowfilter; |
| Table Joins | Cross Inner / Natural Outer( Left Right Full) |