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| 5842151922 | What is a database? | A database is a structured set of data held in a computer, especially one that is accessible in various ways. |  | 0 |
| 5842151923 | What is a field? | A field in a record that holds unique data which identifies that record from all the other records in the file or database. |  | 1 |
| 5842151924 | What is a record? | A complete row of information about a person or thing. |  | 2 |
| 5842151925 | What is a flat file? | A database that holds all the information in one file. |  | 3 |
| 5842151926 | What is a relational database? | A database comprised of linked tables. |  | 4 |
| 5842151927 | A relational database allows you to save space. [True] / [False] | True. | 5 | |
| 5842151928 | A relational database causes data redundancy by making you repeat data entries. [True] / [False] | False. | 6 | |
| 5842151929 | A relational database helps you avoid making data entry mistakes. [True] / [False] | True. | 7 | |
| 5842151930 | Database | Contains information in fields and columns |  | 8 |
| 5842151931 | Filing Cabinet | Is an old database |  | 9 |
| 5842151932 | Data Field | Information about one specific thing. Example 'Artist' or 'Surname' | 10 | |
| 5842151933 | Record | A ______________________ is a collection of fields, possibly of different data types. |  | 11 |
| 5842151934 | What is a FLAT FILE? | A file having no internal structure. No other file is more important than the other. | | 12 |
| 5842151935 | Relational Database | A database structured to recognize relations between stored items of information. | 13 | |
| 5842151936 | A database allows you to save space? TRUE or FALSE? | True | 14 | |
| 5842151937 | To make a search better. | Add more information about the person you are looking for. | 15 | |
| 5842151938 | Goal | Old English word meaning Jail | 16 | |
| 5842151939 | File | Something containing data stored on a computer. | 17 | |
| 5842151940 | DBMS | Database management system | 18 | |
| 5842151941 | A Record Row | Goes across a database | | 19 |
| 5842151942 | An example of a database | iTunes | 20 | |
| 5842151943 | An example of a non-digital database | The Yellow pages | 21 | |
| 5842151944 | Database | maintains information about various types of objects (inventory), events (transactions), people (employees), and places (warehouses) | 22 | |
| 5842151945 | Database management system (DBMS) | creates, reads, updates, and deletes data in a database while controlling access and security | 23 | |
| 5842151946 | Relational database model | a type of database that stores its information in the form of logically-related two-dimensional tables | 24 | |
| 5842151947 | process model | formal way of representing how a business operates by looking at the system itself versus users. Ultimately, guides what code must do | 25 | |
| 5842151948 | Data model | The logical data structure that details the relationships among data elements using graphics or pictures | 26 | |
| 5842151949 | Entity Relationship (ER) diagram | consists of entities, attributes and relationships | 27 | |
| 5842151950 | Entity | Also called a Table (in MSAccess), stores information about a person, place, thing, transaction, or event | 28 | |
| 5842151951 | Instance | the representation of a particular entity, i.e. STUDENT(John Smith, 123-45-6789) | 29 | |
| 5842151952 | Entity Examples | Wine Club Member, employee, wine, customer, product | 30 | |
| 5842151953 | Attributes | data elements associated with an entity ( Customer - name, address, number... Item - item number, price, genre) | 31 | |
| 5842151954 | There are several types of attributes including | Stored versus derived (DOB-12-Jan-1987 vs. current age), Null-valued (no home phone number), Simple versus composite, single-valued versus multi-valued | 32 | |
| 5842151955 | Simple Attributes | Attributes that are not divisible into subparts | 33 | |
| 5842151956 | Composite attributes | can be divided into smaller subparts, which represent more basic attributes that have their own meanings | 34 | |
| 5842151957 | Single-valued attribute | having only a single value of each attribute of an entity at any given time | 35 | |
| 5842151958 | Multi-valued attribute | having the potential to contain more than one value for an attribute at any given time | 36 | |
| 5842151959 | Identifiers | Primary keys and foreign keys identify the various entity classes (tables) in the database, i.e. StudentIDNumber, SSAN, AutoNumber. | 37 | |
| 5842151960 | Primary key | a field (or group of fields) that uniquely identifies a given entity in a table. Two qualities of all primary keys: A primary key should contain some value that is highly unlikely ever to be null A primary key should never change | 38 | |
| 5842151961 | Foreign key | a primary key of one table that appears an attribute in another table and acts to provide a logical relationship among the two tables | 39 | |
| 5842151962 | Cardinality | expresses the specific number of entity occurrences associated with one occurrence of the related entity | 40 | |
| 5842151963 | Composite entities | Entities that exist to represent the relationship between two other entities. Customer buys Products and Products can be purchased by many customers. Below is a Many-to-Many Relationship |  | 41 |
| 5842151964 | theta-join | A theta-join is a binary operation that combines two relations where the combination of rows satisfies a predicate. A theta-join can be viewed in terms of a restricted Cartesian product operation. Any of the comparison operators can be used in the predicate. If the predicate contains only the equality operator, the join is known as an equi-join. | 42 | |
| 5842151965 | Which type of join shows rows in the first relation even if they have no matching values in the shared column of the second relation? | Left outer join | 43 | |
| 5842151966 | natural join | A natural join is a binary operation that combines two relations over their common attributes, eliminating one occurrence of each common attribute. | 44 | |
| 5842151967 | Right outer join | On occasion, when joining two relations based on matching values in a join column, you will want rows to appear in the result relation even though no matching values occur in the second relation. Outer join operations make this possible. Several types of outer joins exist. In a left outer join, a binary operation, rows from the first relation that do not have matching values in the shared column of the second relation are included in the result relation. Right outer joins keep every unmatched row in the second relation in the result relation. | 45 | |
| 5842151968 | In regard to serializability, which of the following is true? | When determining serializability, you must consider the following: If concurrent transactions only read data, no conflict exists and the order of execution is not significant. If concurrent transactions read or write entirely different data structures, no conflict exists and the order of execution is not significant. If concurrent transactions read or write the same data structures, the order of execution is significant. | 46 | |
| 5842151969 | Inner Join | An inner join only returns those records that have "matches" in both tables. So for every record returned in T1 - you will also get the record linked by the foreign key in T2. In programming logic - think in terms of AND. | 47 | |
| 5842151970 | Outer Join | An outer join is the inverse of the inner join. It only returns those records not in T1 and T2. "Give me the records that DON'T have a match." In programming logic - think in terms of NOT AND. | 48 | |
| 5842151971 | Left Join | A left join returns all the records in the "left" table (T1) whether they have a match in the right table or not. If, however, they do have a match in the right table - give me the "matching" data from the right table as well. If not - fill in the holes with null. | 49 | |
| 5842151972 | LEFT OUTER JOIN | A left outer join combines the ideas behind a left join and an outer join. Basically - if you use a left outer join you will get the records in the left table that DO NOT have a match in the right table. | 50 | |
| 5842151973 | Theta JOIN | A theta join is the Cartesian product of the 2 tables and not normally what people are looking for - but what they sometimes get by mistake. How many of us have written a join similar to this only to get way more then we were ever expecting. |  | 51 |
| 5842151974 | Entity | 52 | ||
| 5842151975 | Field | Data and information of someone or something. | 53 | |
| 5842151976 | Record | All information of someone or something in a line. | 54 | |
| 5842151977 | Flat File | A data that contains information without structures. | 55 | |
| 5842151978 | Relational Database | Data that are organised formally for many ways. | 56 | |
| 5842151979 | Advantage of Relational Database | Data is only stored once so that storage are easily efficient, if the user wants to delete then it is easy and links are easy. | 57 | |
| 5842151980 | Primary Key | Unique number that helps to tell each record apart. | 58 | |
| 5842151981 | Data Type of a Primary Key | Auto Number- so the computer automatically generates the number. | 59 | |
| 5842151982 | Data Types | 1. Text- Letters, numbers, punctuation. 2. Number- Numbers only. 3.Date/Time- Dates or times. | 60 | |
| 5842151983 | Validation Check | The way the computer checks if the data that is entered is sensible and reasonable. |  | 61 |
| 5842151984 | Presence Check | See if data has been properly entered. For example are letters and numbers. |  | 62 |
| 5842151985 | Length Check | Check the data if it has the same number open. This are like passwords. |  | 63 |
| 5842151986 | Range Check | Check that the value entered is determined. |  | 64 |
| 5842151987 | Type Check | Make sure the data is correct. |  | 65 |
| 5842151988 | Check Digit | Allows a number to be checked. For example is a calculator. |  | 66 |
| 5842151989 | Format Check | Make sure a data is in correct format. This is like postcodes. |  | 67 |
| 5842151990 | Lookup Check | This compares a data like an address. |  | 68 |
| 5842151991 | Verification | Checks for human error so that it makes sure the user did not get a typo. For example: passwords and captcha. |  | 69 |
