Structured Query Language (SQL)
... accessing, and managing relational databases. • In 1970, E.F. Codd at IBM Research Labs in San Jose, California published “A Relational Model of Data for Large Shared Data Banks” (Communications of the ACM, Vol. 13, No. 6, June 1970) in which he described a set of abstract principles for database ma ...
... accessing, and managing relational databases. • In 1970, E.F. Codd at IBM Research Labs in San Jose, California published “A Relational Model of Data for Large Shared Data Banks” (Communications of the ACM, Vol. 13, No. 6, June 1970) in which he described a set of abstract principles for database ma ...
Slides
... An Integrity Constraint (IC) describes conditions that every legal instance of a relation must satisfy Inserts/deletes/updates that violate IC’s are disallowed ICs can be used to: Ensure application semantics (e.g., sid is a key) Prevent inconsistencies (e.g., sname has to be a string, age ...
... An Integrity Constraint (IC) describes conditions that every legal instance of a relation must satisfy Inserts/deletes/updates that violate IC’s are disallowed ICs can be used to: Ensure application semantics (e.g., sid is a key) Prevent inconsistencies (e.g., sname has to be a string, age ...
Open Database
... add Order Detail and Products tables, set product name = "Tofu" as a selection criterion OPTIONAL: Ask students to find all employees who handled an order for a specific customer (e.g. "North/South") Totals (name for queries using aggregate functions) Select “View” then “Totals”. This inserts a row ...
... add Order Detail and Products tables, set product name = "Tofu" as a selection criterion OPTIONAL: Ask students to find all employees who handled an order for a specific customer (e.g. "North/South") Totals (name for queries using aggregate functions) Select “View” then “Totals”. This inserts a row ...
Relational Database
... Order is ASC(default) or DESC Can have major and minor orders CLUSTER specification keeps records with same value for indexed field together (only one per table) Oracle automatically indexes primary key columns ...
... Order is ASC(default) or DESC Can have major and minor orders CLUSTER specification keeps records with same value for indexed field together (only one per table) Oracle automatically indexes primary key columns ...
Escape from the Data Warehouse Death March
... Intro to Sql Joins with Stars • The Issue: What if the selection criteria is spread among the Dimension tables. • That is, the query as a whole only returns a few rows, but the ‘Where Clause” on each Dimension table is not very restrictive. • This presents a special type of problem, and the join me ...
... Intro to Sql Joins with Stars • The Issue: What if the selection criteria is spread among the Dimension tables. • That is, the query as a whole only returns a few rows, but the ‘Where Clause” on each Dimension table is not very restrictive. • This presents a special type of problem, and the join me ...
Computer Programming Lab II - The Institute of Finance
... integers and reals. o = overall number of digits, d = number of digits to the right of the decimal point. date: Date data type for storing date and time. long: Character data up to a length of ...
... integers and reals. o = overall number of digits, d = number of digits to the right of the decimal point. date: Date data type for storing date and time. long: Character data up to a length of ...
Attribute Data and Relational Database
... fields in the table as the primary key if that field would never contain duplicate values for the different records. An example of a good choice would be the social security number field. If none of the fields are suitable, the program can add a counter field that will automatically assign a unique ...
... fields in the table as the primary key if that field would never contain duplicate values for the different records. An example of a good choice would be the social security number field. If none of the fields are suitable, the program can add a counter field that will automatically assign a unique ...
Querying Database - San Francisco State University
... • Projection operation defines a vertical subset of a table and retrieves only the specified fields. • Example: Customer table: CID, Cname, City, Rating – Create a query to show CID, Cname, Rating – Create a query to show CID, Cname, City ...
... • Projection operation defines a vertical subset of a table and retrieves only the specified fields. • Example: Customer table: CID, Cname, City, Rating – Create a query to show CID, Cname, Rating – Create a query to show CID, Cname, City ...
Querying Database - San Francisco State University
... – Query design tools/Total – A Total row is added to the design view – Select function from the total row’s dropdown list ...
... – Query design tools/Total – A Total row is added to the design view – Select function from the total row’s dropdown list ...
Introduction to ERwin
... • “Always” use Integer and Identity(1,1) for Primary Keys. Use UNIQUE constraint for other columns that needs to be unique, e.g. “RoomNumber” • Specify Required Columns (NOT NULL) – i.e., which columns that need to have data or not ...
... • “Always” use Integer and Identity(1,1) for Primary Keys. Use UNIQUE constraint for other columns that needs to be unique, e.g. “RoomNumber” • Specify Required Columns (NOT NULL) – i.e., which columns that need to have data or not ...
Lecture slides
... Sometimes we have to select data from two tables to make our result complete. We have to perform a join. Tables in a database can be related to each other with keys. – A primary key is a column with a unique value for each row. The purpose is to bind data together, across tables, without repeating a ...
... Sometimes we have to select data from two tables to make our result complete. We have to perform a join. Tables in a database can be related to each other with keys. – A primary key is a column with a unique value for each row. The purpose is to bind data together, across tables, without repeating a ...
FIT100 - Faculty
... the places where it is needed - Keep data in its own table - Save its key wherever it is needed When users want the data, get it using its key! ...
... the places where it is needed - Keep data in its own table - Save its key wherever it is needed When users want the data, get it using its key! ...
X-Data: Test Data Generation for Killing SQL Mutants
... Join type mutations: An occurrence of a join operator ( , , , ) is replaced by one of the other join operators Defining join mutations in SQL is complicated by the absence of a particular join order SELECT * FROM a,b,c WHERE (a.x = b.x) and (b.x = c.x) ...
... Join type mutations: An occurrence of a join operator ( , , , ) is replaced by one of the other join operators Defining join mutations in SQL is complicated by the absence of a particular join order SELECT * FROM a,b,c WHERE (a.x = b.x) and (b.x = c.x) ...
Active Data Objects in .Net
... A relational database is composed of one or more (usually more) tables. Each table consists of rows and columns. – A row is referred to as a record • A record refers to a single entity – person, place, or thing • Each record in the database is unique, no duplicates are allowed ...
... A relational database is composed of one or more (usually more) tables. Each table consists of rows and columns. – A row is referred to as a record • A record refers to a single entity – person, place, or thing • Each record in the database is unique, no duplicates are allowed ...
10 Web Servers PHP MySQL
... if (! ($database = mysql_connect ("localhost", "user", "password"))) { // die ("Can't use database.
... if (! ($database = mysql_connect ("localhost", "user", "password"))) { // die ("Can't use database.