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What is the primary responsibility of a database administrator?
What is the primary responsibility of a database administrator?
What is the main function of the query processor in a database system?
What is the main function of the query processor in a database system?
What is the purpose of the storage manager in a database system?
What is the purpose of the storage manager in a database system?
What is the role of the transaction manager in a database system?
What is the role of the transaction manager in a database system?
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Which type of table is particularly fast for bulk load of many rows?
Which type of table is particularly fast for bulk load of many rows?
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What kind of function is the modulo function in a hash table?
What kind of function is the modulo function in a hash table?
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What is the percentage of table rows selected by a query known as?
What is the percentage of table rows selected by a query known as?
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What type of index contains an entry for every table row?
What type of index contains an entry for every table row?
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Which database object maps one or more tables to a single file?
Which database object maps one or more tables to a single file?
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What does logical design specify in a database?
What does logical design specify in a database?
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What does a storage engine or storage manager translate into low-level commands?
What does a storage engine or storage manager translate into low-level commands?
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What SQL statement is used to create an index?
What SQL statement is used to create an index?
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Which statement best describes the responsibility of a transaction manager?
Which statement best describes the responsibility of a transaction manager?
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Which operation is supported by MongoDB?
Which operation is supported by MongoDB?
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What does the SQL's CREATE TABLE statement do?
What does the SQL's CREATE TABLE statement do?
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What is the purpose of the logical design phase in database design?
What is the purpose of the logical design phase in database design?
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What is the main function of an application programming interface (API) like MySQL Command-Line Client?
What is the main function of an application programming interface (API) like MySQL Command-Line Client?
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What is a tuple in the context of databases?
What is a tuple in the context of databases?
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What are business rules based on in the context of databases?
What are business rules based on in the context of databases?
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Which SQL data type has the largest storage size and range among the given options?
Which SQL data type has the largest storage size and range among the given options?
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Which SQL operator is used for exponentiation?
Which SQL operator is used for exponentiation?
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What SQL statement is used for deleting all rows in a table?
What SQL statement is used for deleting all rows in a table?
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In SQL, what does a foreign key constraint ensure?
In SQL, what does a foreign key constraint ensure?
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Which SQL constraint is used to enforce data validation rules on a table?
Which SQL constraint is used to enforce data validation rules on a table?
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Which SQL keyword is used to modify table data and structure?
Which SQL keyword is used to modify table data and structure?
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What is a high-level representation of data requirements in SQL that includes entities, relationships, and attributes?
What is a high-level representation of data requirements in SQL that includes entities, relationships, and attributes?
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What does a reflexive relationship relate in SQL?
What does a reflexive relationship relate in SQL?
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Which SQL join combines each row from the first table with every row from the second table?
Which SQL join combines each row from the first table with every row from the second table?
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What does a primary key constraint prevent in SQL?
What does a primary key constraint prevent in SQL?
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In SQL, what does the % operator calculate?
In SQL, what does the % operator calculate?
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Which clause is used in SQL to specify the conditions that must be met for the records to be selected during a query?
Which clause is used in SQL to specify the conditions that must be met for the records to be selected during a query?
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In an entity-relationship diagram (ER diagram), how are entities represented?
In an entity-relationship diagram (ER diagram), how are entities represented?
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What does cardinality refer to in an ER diagram?
What does cardinality refer to in an ER diagram?
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What is the purpose of primary keys in a table?
What is the purpose of primary keys in a table?
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What is the first step in creating an ER diagram?
What is the first step in creating an ER diagram?
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What does data modeling progress through after analysis in the context of ER diagrams?
What does data modeling progress through after analysis in the context of ER diagrams?
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What is the relationship between one column and another in the context of functional dependence?
What is the relationship between one column and another in the context of functional dependence?
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How are subtype entities documented within the supertype entity in an ER diagram?
How are subtype entities documented within the supertype entity in an ER diagram?
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What does normalization aim to achieve in a table?
What does normalization aim to achieve in a table?
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Which notation is used in ER diagrams to depict cardinality?
Which notation is used in ER diagrams to depict cardinality?
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What happens when tables are in various normal forms?
What happens when tables are in various normal forms?
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What does a primary key represent for a table?
What does a primary key represent for a table?
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What is the role of an intangible entity in a database?
What is the role of an intangible entity in a database?
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Study Notes
- An entity-relationship diagram (ER diagram) is a visual representation of entities, relationships, and attributes
- Entities are represented as rectangles, with types being sets of things (e.g., all employees in a company) and instances being individual things (e.g., the employee Sam Snead)
- Types of entities include entity types (sets of things) and relationship types (sets of related things)
- Attributes are represented as sets of values and are usually transformed into tables, columns, and keys, respectively
- Analysis is the first step in creating an ER diagram, during which entities, relationships, and attributes are discovered
- Cardinality refers to the maximum and minimum number of instances of one entity that can relate to a single instance of another entity
- Subtype entities are a subset of a supertype entity and are documented within the supertype entity in an ER diagram
- Primary keys are unique identifiers for a table that should be stable, simple, and meaningless
- Data modeling progresses through steps of analysis, logical design, and physical design
- Functional dependence is the relationship between one column and another, and normalization is the process of eliminating redundancy in a table
- ER diagrams use crow's foot notation to depict cardinality
- An intangible entity is documented but not tracked with data in the database
- Tables can be in various normal forms (e.g., third normal form, Boyce-Codd normal form) to minimize redundancy
- Trivial dependencies occur when one column is a subset of another, and normalization eliminates this redundancy
- Databases can have different table structures, such as heap tables with no imposed order on rows.
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Description
Test your knowledge on data types and their ranges with this quiz. From TINYINT to BIGINT, this quiz covers the different integer data types and their storage capacities.