SQL Server/T-SQL Tutorial/Query/Column Alias — различия между версиями

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м (1 версия)
 
м (1 версия)
 
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Текущая версия на 10:23, 26 мая 2010

Alias a column: Alias = Column

7> CREATE TABLE employee(
8>    id          INTEGER NOT NULL PRIMARY KEY,
9>    first_name  VARCHAR(10),
10>    last_name   VARCHAR(10),
11>    salary      DECIMAL(10,2),
12>    start_Date  DATETIME,
13>    region      VARCHAR(10),
14>    city        VARCHAR(20),
15>    managerid   INTEGER
16> );
17> GO
1> INSERT INTO employee VALUES (1, "Jason" ,  "Martin", 5890,"2005-03-22","North","Vancouver",3);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (2, "Alison",  "Mathews",4789,"2003-07-21","South","Utown",4);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (3, "James" ,  "Smith",  6678,"2001-12-01","North","Paris",5);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (4, "Celia" ,  "Rice",   5567,"2006-03-03","South","London",6);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (5, "Robert",  "Black",  4467,"2004-07-02","East","Newton",7);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (6, "Linda" ,  "Green" , 6456,"2002-05-19","East","Calgary",8);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (7, "David" ,  "Larry",  5345,"2008-03-18","West","New York",9);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (8, "James" ,  "Cat",    4234,"2007-07-17","West","Regina",9);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (9, "Joan"  ,  "Act",    6123,"2001-04-16","North","Toronto",10);
2> GO
(1 rows affected)
1>
2> select * from employee;
3> GO
id          first_name last_name  salary       start_Date              region     city                 managerid
----------- ---------- ---------- ------------ ----------------------- ---------- -------------------- -----------
          1 Jason      Martin          5890.00 2005-03-22 00:00:00.000 North      Vancouver                      3
          2 Alison     Mathews         4789.00 2003-07-21 00:00:00.000 South      Utown                          4
          3 James      Smith           6678.00 2001-12-01 00:00:00.000 North      Paris                          5
          4 Celia      Rice            5567.00 2006-03-03 00:00:00.000 South      London                         6
          5 Robert     Black           4467.00 2004-07-02 00:00:00.000 East       Newton                         7
          6 Linda      Green           6456.00 2002-05-19 00:00:00.000 East       Calgary                        8
          7 David      Larry           5345.00 2008-03-18 00:00:00.000 West       New York                       9
          8 James      Cat             4234.00 2007-07-17 00:00:00.000 West       Regina                         9
          9 Joan       Act             6123.00 2001-04-16 00:00:00.000 North      Toronto                       10
(9 rows affected)
1>
2> SELECT FullName = First_Name + " " + Last_Name
3> FROM Employee;
4> GO
FullName
---------------------
Jason Martin
Alison Mathews
James Smith
Celia Rice
Robert Black
Linda Green
David Larry
James Cat
Joan Act
(9 rows affected)
1>
2>
3>
4> drop table employee;
5> GO


Alias a column: Column Alias

8> CREATE TABLE employee(
9>    id          INTEGER NOT NULL PRIMARY KEY,
10>    first_name  VARCHAR(10),
11>    last_name   VARCHAR(10),
12>    salary      DECIMAL(10,2),
13>    start_Date  DATETIME,
14>    region      VARCHAR(10),
15>    city        VARCHAR(20),
16>    managerid   INTEGER
17> );
18> GO
1> INSERT INTO employee VALUES (1, "Jason" ,  "Martin", 5890,"2005-03-22","North","Vancouver",3);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (2, "Alison",  "Mathews",4789,"2003-07-21","South","Utown",4);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (3, "James" ,  "Smith",  6678,"2001-12-01","North","Paris",5);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (4, "Celia" ,  "Rice",   5567,"2006-03-03","South","London",6);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (5, "Robert",  "Black",  4467,"2004-07-02","East","Newton",7);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (6, "Linda" ,  "Green" , 6456,"2002-05-19","East","Calgary",8);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (7, "David" ,  "Larry",  5345,"2008-03-18","West","New York",9);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (8, "James" ,  "Cat",    4234,"2007-07-17","West","Regina",9);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (9, "Joan"  ,  "Act",    6123,"2001-04-16","North","Toronto",10);
2> GO
(1 rows affected)
1>
2> select * from employee;
3> GO
id          first_name last_name  salary       start_Date              region     city                 managerid
----------- ---------- ---------- ------------ ----------------------- ---------- -------------------- -----------
          1 Jason      Martin          5890.00 2005-03-22 00:00:00.000 North      Vancouver                      3
          2 Alison     Mathews         4789.00 2003-07-21 00:00:00.000 South      Utown                          4
          3 James      Smith           6678.00 2001-12-01 00:00:00.000 North      Paris                          5
          4 Celia      Rice            5567.00 2006-03-03 00:00:00.000 South      London                         6
          5 Robert     Black           4467.00 2004-07-02 00:00:00.000 East       Newton                         7
          6 Linda      Green           6456.00 2002-05-19 00:00:00.000 East       Calgary                        8
          7 David      Larry           5345.00 2008-03-18 00:00:00.000 West       New York                       9
          8 James      Cat             4234.00 2007-07-17 00:00:00.000 West       Regina                         9
          9 Joan       Act             6123.00 2001-04-16 00:00:00.000 North      Toronto                       10
(9 rows affected)
1>
2>
3> SELECT First_Name + " " + Last_Name FullName
4> FROM Employee;
5> GO
FullName
---------------------
Jason Martin
Alison Mathews
James Smith
Celia Rice
Robert Black
Linda Green
David Larry
James Cat
Joan Act
(9 rows affected)
1>
2> drop table employee;
3> GO
1>
2>
3>


A SELECT statement that doesn"t provide a name for a calculated column

4>
5>
6> create table Billings (
7>     BankerID           INTEGER,
8>     BillingNumber      INTEGER,
9>     BillingDate        datetime,
10>     BillingTotal       INTEGER,
11>     TermsID            INTEGER,
12>     BillingDueDate     datetime ,
13>     PaymentTotal       INTEGER,
14>     CreditTotal        INTEGER
15>
16> );
17> GO
1>
2> INSERT INTO Billings VALUES (1, 1, "2005-01-22", 165, 1,"2005-04-22",123,321);
3> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (2, 2, "2001-02-21", 165, 1,"2002-02-22",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (3, 3, "2003-05-02", 165, 1,"2005-04-12",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (4, 4, "1999-03-12", 165, 1,"2005-04-18",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (5, 5, "2000-04-23", 165, 1,"2005-04-17",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (6, 6, "2001-06-14", 165, 1,"2005-04-18",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (7, 7, "2002-07-15", 165, 1,"2005-04-19",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (8, 8, "2003-08-16", 165, 1,"2005-04-20",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (9, 9, "2004-09-17", 165, 1,"2005-04-21",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (0, 0, "2005-10-18", 165, 1,"2005-04-22",123,321);
2> GO
(1 rows affected)
1>
2>
3> SELECT BillingNumber, BillingDate, BillingTotal,
4>     BillingTotal - PaymentTotal - CreditTotal
5> FROM Billings
6> GO
BillingNumber BillingDate             BillingTotal
------------- ----------------------- ------------ -----------
            1 2005-01-22 00:00:00.000          165        -279
            2 2001-02-21 00:00:00.000          165        -279
            3 2003-05-02 00:00:00.000          165        -279
            4 1999-03-12 00:00:00.000          165        -279
            5 2000-04-23 00:00:00.000          165        -279
            6 2001-06-14 00:00:00.000          165        -279
            7 2002-07-15 00:00:00.000          165        -279
            8 2003-08-16 00:00:00.000          165        -279
            9 2004-09-17 00:00:00.000          165        -279
            0 2005-10-18 00:00:00.000          165        -279
(10 rows affected)
1>
2> drop table Billings;
3> GO


A SELECT statement that uses the AS keyword (the preferred technique)

3>
4>
5> create table Billings (
6>     BankerID           INTEGER,
7>     BillingNumber      INTEGER,
8>     BillingDate        datetime,
9>     BillingTotal       INTEGER,
10>     TermsID            INTEGER,
11>     BillingDueDate     datetime ,
12>     PaymentTotal       INTEGER,
13>     CreditTotal        INTEGER
14>
15> );
16> GO
1>
2> INSERT INTO Billings VALUES (1, 1, "2005-01-22", 165, 1,"2005-04-22",123,321);
3> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (2, 2, "2001-02-21", 165, 1,"2002-02-22",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (3, 3, "2003-05-02", 165, 1,"2005-04-12",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (4, 4, "1999-03-12", 165, 1,"2005-04-18",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (5, 5, "2000-04-23", 165, 1,"2005-04-17",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (6, 6, "2001-06-14", 165, 1,"2005-04-18",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (7, 7, "2002-07-15", 165, 1,"2005-04-19",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (8, 8, "2003-08-16", 165, 1,"2005-04-20",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (9, 9, "2004-09-17", 165, 1,"2005-04-21",123,321);
2> GO
(1 rows affected)
1> INSERT INTO Billings VALUES (0, 0, "2005-10-18", 165, 1,"2005-04-22",123,321);
2> GO
(1 rows affected)
1>
2>
3> SELECT BillingNumber AS [Billing Number], BillingDate AS Date,BillingTotal AS Total
4> FROM Billings
5> GO
Billing Number Date                    Total
-------------- ----------------------- -----------
             1 2005-01-22 00:00:00.000         165
             2 2001-02-21 00:00:00.000         165
             3 2003-05-02 00:00:00.000         165
             4 1999-03-12 00:00:00.000         165
             5 2000-04-23 00:00:00.000         165
             6 2001-06-14 00:00:00.000         165
             7 2002-07-15 00:00:00.000         165
             8 2003-08-16 00:00:00.000         165
             9 2004-09-17 00:00:00.000         165
             0 2005-10-18 00:00:00.000         165
(10 rows affected)
1>
2>
3> drop table Billings;
4> GO


create an alias column called SubCategory.

7> CREATE TABLE Product(
8>     ProductID               int                NOT NULL,
9>     Name                    nvarchar(25)       NOT NULL,
10>     ProductNumber           nvarchar(25)               ,
11>     Color                   nvarchar(15)       NULL,
12>      StandardCost            money              NOT NULL,
13>      Size                    nvarchar(5)        NULL,
14>      Weight                  decimal(8, 2)      NULL,
15>      ProductLine             nchar(20)           NULL,
16>      SellStartDate           datetime           NOT NULL,
17>      SellEndDate             datetime           NULL
18>  )
19>  GO
1> insert into Product values(1,"Product A", "1","Red",123.123,"1",1,"ProductLine A","1999-03-22","2000-03-22");
2> GO
(1 rows affected)
1>
2>
3> insert into Product values(2,"Product B", "2","Yellow",234.234,"1",3,"ProductLine B","2000-03-22","2001-03-22");
4> GO
(1 rows affected)
1>
2>
3> insert into Product values(3,"Product C", "3","Pink",345.345,"1",3,"ProductLine V","2001-09-22","2006-02-22");
4> GO
(1 rows affected)
1>
2>
3> insert into Product values(4,"Product D", "4","White",456.456,"1",4,"ProductLine D","2002-08-22","2006-03-22");
4> GO
(1 rows affected)
1>
2>
3> insert into Product values(5,"Product E", "5","Black",567.567,"1",5,"ProductLine E","2003-01-22","2003-04-22");
4> GO
(1 rows affected)
1>
2>
3> insert into Product values(6,"Product F", "6","Blue",678.678,"1",6,"ProductLine W","2004-02-22","2005-05-22");
4> GO
(1 rows affected)
1>
2>
3> insert into Product values(7,"Product G", "7","Drak",789.789,"1",7,"ProductLine Q","2005-03-22","2006-03-22");
4> GO
(1 rows affected)
1>
2>
3> insert into Product values(8,"Product H", "8","Gray",234.123,"1",8,"ProductLine F","2006-04-22","2006-09-22");
4> GO
(1 rows affected)
1>
2>
3> insert into Product values(9,"Product I", "9","Red",543.123,"1",9,"ProductLine R","2007-05-22","2008-03-22");
4> GO
(1 rows affected)
1>
2>
3> insert into Product values(0,"Product J", "0","Gold",765.123,"1",0,"ProductLine J","2008-06-22","2009-03-22");
4> GO
(1 rows affected)
1>
2>
3>
4>
5>
6> SELECT ProductID
7>  , Name
8>  , SubCategory = CASE ProductID
9>    WHEN 1 THEN "Mountain Bike"
10>    WHEN 2 THEN "Road Bike"
11>     WHEN 3 THEN "Touring Bike"
12>     WHEN Null THEN "Something Else"
13>     ELSE "(No Subcategory)"
14>   END
15>  FROM Product
16>  GO
ProductID   Name                      SubCategory
----------- ------------------------- ----------------
          1 Product A                 Mountain Bike
          2 Product B                 Road Bike
          3 Product C                 Touring Bike
          4 Product D                 (No Subcategory)
          5 Product E                 (No Subcategory)
          6 Product F                 (No Subcategory)
          7 Product G                 (No Subcategory)
          8 Product H                 (No Subcategory)
          9 Product I                 (No Subcategory)
          0 Product J                 (No Subcategory)
(10 rows affected)
1>
2>
3> drop table Product;
4> GO