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SQL- Standard Query Language

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Section 1

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WITH

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Date created

Mar 1, 2020

Cards (27)

Section 1

(27 cards)

WITH

Front

allows us to define one or more temporary tables that can be used in the final query. Do not use ; or , within the ( )

Back

MAX( )/ MIN( ):

Front

the largest / smallest value

Back

Database

Front

a place where info is stored; physical/ cloud; the back end; It tells a story, predicts the future, it never goes away.

Back

One to One

Front

when 1 entity is related to another 1 entity; ex: You to Me

Back

Foreign Key

Front

is a column that contains the primary key to another table.

Back

Data Type

Front

the form of data in a record: INT - integer FLOAT/DOUBLE - Decimal TEXT - words (and more)

Back

Many to Many

Front

When more than one entity is related to more than one entity; Ex: Kindergarten to Toys

Back

Field

Front

Item in the record /cell

Back

ROUND( )

Front

: round the values in the column

Back

One to Many

Front

When 1 entity is related to more than one entity; ex: Mother to Children / Teacher to classroom

Back

Record

Front

a set of data with a single object or person; data in each record is different

Back

NULL

Front

values are used to fill in the columns (if empty or not applicable.

Back

Field Name

Front

column name

Back

Flat File

Front

Contains only a single table

Back

COUNT( ):

Front

function that takes the name of a column as an argument and counts the number of non-empty values in that column.

Back

JOIN

Front

will combine rows from different tables if the join condition is true.

Back

CROSS JOIN

Front

lets us combine all rows of one table with all rows of another table.

Back

SUM( ):

Front

function that takes the name of a column as an argument and returns the sum of all the values in that column.

Back

Attribute

Front

a quality that identifies something unique about the entity. For example: entity = dog attributes= brown, shaggy, stinky, hyper

Back

Primary key

Front

is a column that serves a unique identifier for the rows in the table.

Back

Entity

Front

a person or thing

Back

LEFT JOIN

Front

will return every row in the left table, and if the join condition is not met; no data.

Back

Relationships

Front

one to one, one to many, many to many

Back

AVG( )

Front

: the average of the values in a column

Back

SELECT (Column) FROM (table)

Front

allows you to query columns with no duplicates

Back

Relational Databases

Front

2 or more tables of data connected by links called relationships

Back

UNION

Front

stacks one dataset on top of another.

Back