sql SELECT and SELECT DISTINCT

The SQL SELECT satement is used to select data from a database table.

The following is the SQL SELECT syntax:


SELECT * FROM myTable


The statement will retrieve all data on all of myTable columns.

If only specified columns are to be viewed, use the following syntax:


SELECT myColumn1, myColumn2, myColumn3 FROM myTable


The SQL DISTINCT keyword returns a list of distinct values only (duplicate values are not displayed).

SQL SELECT DISTINCT syntax:


SELECT DISTINCT myColumn FROM myTable


SQL date select statement, part 6

The following SELECT statements would give you the equivalent date value:

YYYYMMDD

SELECT CONVERT(varchar(20),getdate(),112)


DD MMM YYY HH:MM:SS:MMM

SELECT CONVERT(varchar(30),getdate(),113)


HH:MM:SS:MMM

SELECT CONVERT(varchar(30),getdate(),114)


YYYY-MM-DD HH:MM:SS

SELECT CONVERT(varchar(30),getdate(),120)


SQL date select statement, part 5

The following SELECT statements would give you the equivalent date value:

DD MMM YYYY

SELECT CONVERT(varchar(20),getdate(),106)


MMM DD, YYYY

SELECT CONVERT(varchar(20),getdate(),107)


HH:MM:SS

SELECT CONVERT(varchar(20),getdate(),108)


MMM DD YYY H:MM:SS AM/PM

SELECT CONVERT(varchar(30),getdate(),109)


MM/DD/YYYY

SELECT CONVERT(varchar(20),getdate(),110)


YYYY/MM/DD

SELECT CONVERT(varchar(20),getdate(),111)


SQL date select statement, part 4

The following SELECT statements would give you the equivalent date value:

MM/DD/YYYY

SELECT CONVERT(varchar(20),getdate(),101)


MM-DD-YYYY

SELECT REPLACE(convert(varchar(20),getdate(),101),'/','-')


DD/MM/YYYY

SELECT CONVERT(varchar(20),getdate(),103)


DD.MM.YYYY

SELECT CONVERT(varchar(20),getdate(),104)


DD-MM-YYYY

SELECT CONVERT(varchar(20),getdate(),105)


SQL date select statement, part 3

The following SELECT statements would give you the equivalent date value:

Quarter of the year

SELECT DATENAME(QQ, getdate())


Hour of the day

SELECT DATEPART(HH, getdate())


Minute of the hour

SELECT DATEPART(MI, getdate())


Second of the hour

SELECT DATEPART(SS, getdate())


SQL date select statement, part 2

The following SELECT statements would give you the equivalent date value:

Day of the Month

SELECT DATEPART(DD, getdate())


Week of the year

SELECT DATEPART(WW, getdate())


Day of the week

SELECT DATEPART(DW, getdate())


Name of the day

SELECT DATENAME(DW, getdate())


SQL date select statement, part 1

The following SELECT statements would give you the equivalent date value:

Year

SELECT DATEPART(YY, getdate())


Days in a year

SELECT DATEPART(DY, getdate())


Month

SELECT DATEPART(MM, getdate())


Month name

SELECT DATENAME(MM, getdate())


select the first row in sql select statement

The following sql statement will retrieve the first row from a select statement:


SELECT TOP 1 * FROM MY_TABLE ORDER BY THE_PK DESC


select the second row in a select statement

The following code will select the second row in an sql select statement.


SELECT TOP 1 * FROM (SELECT TOP 2 * FROM MY_TBL ORDER BY MY_DATE ASC ) AS VALUE ORDER BY MY_DATE ASC