Post on 25-Dec-2015
Entity / Attributes• Entity represents a person / thing• Entity represents an Access table• Attributes describe facets of an entity• Attributes represents columns in an Access table
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CLIENT
*ClientIDClientName
ClientServicesClientCity
ClientStateClientRevenue
Identifiers / Primary Keys• Every entity must be uniquely identified (via a primary key)• Asterisk represents the primary key• A primary key can be a single attribute or a combination of
attributes• Unique attributes can serve as the primary key (ClientName)• A primary key can be created (ID) in situations where there are
unique attributes
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CLIENT
*ClientIDClientName
ClientServicesClientCity
ClientStateClientRevenue
Example: Client Table
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Client
ClientIDClientName
ClientServices
ClientCity
ClientState
ClientRevenue
1 BK Associates Commercial Portland Oregon $210,000.00
2 Blaloc Industrial Kansas City Missouri $330,000.00
3 Bankton Electric Government New York New York $210,000.00
4 Bick Industrial Raleigh North Carolina $550,000.00
5 TX Electric Government Houston Texas $160,000.00
6 Crow Commercial Dallas Texas $270,000.00
7 GRB Industrial Atlanta Georgia $180,000.00
8 H&P Industrial Denver Colorado $90,000.00
9 LB&B Industrial Boston Massachusetts $211,000.00
10 Congro Industrial Atlanta Georgia $122,000.00
11 Moss Enterprises Commercial Phoenix Arizona $33,000.00
12 Ruby Industrial San Antonio Texas $344,000.00
13 Silver Industries Industrial Omaha Nebraska $218,000.00
14 TPH Commercial Annaheim California $166,000.00
Querying: Client TableTo show all of the data in the Client table.
SELECT * FROM Client;
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ClientIDClientName
ClientServices
ClientCity
ClientState
ClientRevenue
1 BK Associates Commercial Portland Oregon $210,000.00
2 Blaloc Industrial Kansas City Missouri $330,000.00
3 Bankton Electric Government New York New York $210,000.00
4 Bick Industrial Raleigh North Carolina $550,000.00
5 TX Electric Government Houston Texas $160,000.00
6 Crow Commercial Dallas Texas $270,000.00
7 GRB Industrial Atlanta Georgia $180,000.00
8 H&P Industrial Denver Colorado $90,000.00
9 LB&B Industrial Boston Massachusetts $211,000.00
10 Congro Industrial Atlanta Georgia $122,000.00
11 Moss Enterprises Commercial Phoenix Arizona $33,000.00
12 Ruby Industrial San Antonio Texas $344,000.00
13 Silver Industries Industrial Omaha Nebraska $218,000.00
14 TPH Commercial Annaheim California $166,000.00
Selecting Specific Columns (vertical cut)
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Client
ClientIDClientName
ClientServices
ClientCity
ClientState
ClientRevenue
1 BK Associates Commercial Portland Oregon $210,000.00
2 Blaloc Industrial Kansas City Missouri $330,000.00
3 Bankton Electric Government New York New York $210,000.00
4 Bick Industrial Raleigh North Carolina $550,000.00
5 TX Electric Government Houston Texas $160,000.00
6 Crow Commercial Dallas Texas $270,000.00
7 GRB Industrial Atlanta Georgia $180,000.00
8 H&P Industrial Denver Colorado $90,000.00
9 LB&B Industrial Boston Massachusetts $211,000.00
10 Congro Industrial Atlanta Georgia $122,000.00
11 Moss Enterprises Commercial Phoenix Arizona $33,000.00
12 Ruby Industrial San Antonio Texas $344,000.00
13 Silver Industries Industrial Omaha Nebraska $218,000.00
14 TPH Commercial Annaheim California $166,000.00
Selecting Specific Columns (vertical cut)Report a Client’s name, services, and revenues.
Display order based on query (i.e. in order of the comma separators)
SELECT ClientName, ClientServices, ClientRevenue FROM Client;
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ClientName
ClientServices
ClientRevenue
BK Associates Commercial $210,000.00
Blaloc Industrial $330,000.00
Bankton Electric Government $210,000.00
Bick Industrial $550,000.00
TX Electric Government $160,000.00
Crow Commercial $270,000.00
GRB Industrial $180,000.00
H&P Industrial $90,000.00
LB&B Industrial $211,000.00
Congro Industrial $122,000.00
Moss Enterprises Commerical $33,000.00
Ruby Industrial $344,000.00
Silver Industries Industrial $218,000.00
TPH Commercial $166,000.00
Selecting Specific Rows (horizontal cut)
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Client
ClientIDClientName
ClientServices
ClientCity
ClientState
ClientRevenue
1 BK Associates Commercial Portland Oregon $210,000.00
2 Blaloc Industrial Kansas City Missouri $330,000.00
3 Bankton Electric Government New York New York $210,000.00
4 Bick Industrial Raleigh North Carolina $550,000.00
5 TX Electric Government Houston Texas $160,000.00
6 Crow Commercial Dallas Texas $270,000.00
7 GRB Industrial Atlanta Georgia $180,000.00
8 H&P Industrial Denver Colorado $90,000.00
9 LB&B Industrial Boston Massachusetts $211,000.00
10 Congro Industrial Atlanta Georgia $122,000.00
11 Moss Enterprises Commercial Phoenix Arizona $33,000.00
12 Ruby Industrial San Antonio Texas $344,000.00
13 Silver Industries Industrial Omaha Nebraska $218,000.00
14 TPH Commercial Annaheim California $166,000.00
Selecting Specific Rows (horizontal cut)
Show all client data for client that contribute revenue less than $150,000.
SELECT * FROM Client WHERE ClientRevenue < 150000;
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ClientIDClientName
ClientServices
ClientCity
ClientState
ClientRevenue
8 H&P Industrial Denver Colorado $90,000.00
10 Congro Industrial Atlanta Georgia $122,000.00
11 Moss Enterprises Commercial Phoenix Arizona $33,000.00
Selecting Specific Data Within Columns & Rows
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Client
ClientIDClientName
ClientServices
ClientCity
ClientState
ClientRevenue
1 BK Associates Commercial Portland Oregon $210,000.00
2 Blaloc Industrial Kansas City Missouri $330,000.00
3 Bankton Electric Government New York New York $210,000.00
4 Bick Industrial Raleigh North Carolina $550,000.00
5 TX Electric Government Houston Texas $160,000.00
6 Crow Commercial Dallas Texas $270,000.00
7 GRB Industrial Atlanta Georgia $180,000.00
8 H&P Industrial Denver Colorado $90,000.00
9 LB&B Industrial Boston Massachusetts $211,000.00
10 Congro Industrial Atlanta Georgia $122,000.00
11 Moss Enterprises Commercial Phoenix Arizona $33,000.00
12 Ruby Industrial San Antonio Texas $344,000.00
13 Silver Industries Industrial Omaha Nebraska $218,000.00
14 TPH Commercial Annaheim California $166,000.00
Selecting Specific Columns & Rows
Display the Client’s name and revenues where revenue is greater than or equal to $270,000.
SELECT ClientName, ClientRevenue from Client Where ClientRevenue >= 270000;
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ClientName ClientRevenue
Blaloc $330,000.00
Bick $550,000.00
Crow $270,000.00
Ruby $344,000.00
Selecting Specific Cases
List client id, name and state who are based in either Texas or Arizona.SELECT clientID, clientName, clientState FROM Client where clientState = 'Texas' or ClientState = 'Arizona';
also
SELECT clientID, clientName, clientState FROM Client where clientState in ('Texas', 'Arizona');
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clientID clientName clientState
5 TX Electric Texas
6 Crow Texas
11 Moss Enterprises Arizona
12 Ruby Texas
Excluding Specific Cases
List client services and name for clients that provide services that are not Industrial.SELECT ClientServices, ClientName from Client where ClientServices <> 'Industrial';
also
SELECT ClientServices, ClientName from Client where ClientServices Not In ('Industrial');
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ClientServices ClientName
Commercial BK Associates
Government Bankton Electric
Government TX Electric
Commercial Crow
Commercial Moss Enterprises
Commercial TPH
Displaying Output in Order - Columns
SELECT Clientname, ClientState from Client where ClientState = 'North Carolina';
SELECT ClientState, Clientname from Client where ClientState = 'North Carolina';
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Client Name ClientState
Bick North Carolina
ClientState Clientname
North Carolina Bick
Displaying Output in Order - Rows
Display ClientName, ClientCity, ClientRevenue firms where revenues are greater than $180,000 in order of descending revenue. Where revenues are equivalent, list the Client firms in alphabetical order (based on their city).
SELECT ClientName, ClientCity, ClientRevenue FROM Client where ClientRevenue > 180000 order by ClientRevenue desc, ClientCity;
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ClientName ClientCity ClientRevenue
Bick Raleigh $550,000.00
Ruby San Antonio $344,000.00
Blaloc Kansas City $330,000.00
Crow Dallas $270,000.00
Silver Industries Omaha $218,000.00
LB&B Boston $211,000.00
Bankton Electric New York $210,000.00
BK Associates Portland $210,000.00
SQL Functions and Calculations• COUNT, AVG, SUM, MIN, and MAX
Find the average Client RevenueSELECT Avg(ClientRevenue) as AverageRevenue FROM Client;
Display the Client name, state, and revenue (in thousands) for Client from TexasSELECT ClientName, ClientState, ClientRevenue/1000 as ThousandDollars FROM Client Where ClientState = 'Texas';
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AverageRevenue
$221,000.00
ClientName ClientState ThousandDollars
TX Electric Texas 160
Crow Texas 270
Ruby Texas 344
Subqueries
• Subquery = A query within a query
Report all Client names and revenue for those firms with revenues that exceed the average revenue for the group as a whole.
SELECT ClientName, ClientRevenue From Client Where ClientRevenue > (SELECT AVG(ClientRevenue) From Client);
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ClientName ClientRevenue
Blaloc $330,000.00
Bick $550,000.00
Crow $270,000.00
Ruby $344,000.00
Like / Not Like
List all Clients with a name starting with ‘B’.SELECT Clientname FROM Client Where ClientName Like 'B*';
List all Clients have do not have either an ‘S” or ‘B’ in their nameSELECT Clientname FROM Client Where ClientName Not Like '*B*' and
ClientName Not Like '*S*';
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Clientname
BK Associates
Blaloc
Bankton Electric
Bick
Clientname
TX Electric
Crow
H&P
Congro
TPH