In this tutorial i will explain all the basic concepts with syntax and examples :::::::::::::::::::::::::::
SQL SERVER- SQL stands for Structured query language
- Any dbms based on RDBMS use this sql
- IBM developed “system-r” as first DBMS and the actual name is given as “SEQEL”
- But first commercially released by ORACLE company
- ANSI provides standard for SQL
- SQL used in SQL server is called Transact SQL
- Sql is a common language for any RDBMS
- Sql was actually developed by IBM corporation in their project named “System-R”, which is the first RDBMS.
- Actual name given by IBM is ‘SEQUEL’ i.e., structured query language
- But later the name was changed to SQL and was first commercial released by ORACLE corporate
Sql server 2005 features
- High availability: fail over clustering and database mirroring technologies
- management tools: introduce application programming interface[api’s]
- security enhancements: database encryption, more secure default settings, procedure enforcements
- Scalability: table partitioning, replication enhancements, and 64 bit support.
As sql is a common language for any RDBMS,ANSI committee provides a standard for SQL
- The sql that follows the current standard for ANSI committee is called as ‘transact sql’ and sql server uses transact sql as its language
- Sql is a non procedural or 4th generation language
- Sql is not case sensitive
- The commands of sql are classified into:
- data definition language[DDL]:
CREATE,ALTER ,DELETE
- data manipulation language[DML]
INSERT,MODIFY AND DELETE
- data query language[DQL]
SELECT
- data control language[DCL]:CONTROL DATA
GRANT AND REVOKE
- transaction control language[TCL]:MANAGE DATA
COMMIT,ROLLBACK,SAVE
Note:
- single sql can maintain maximum 32,767 databases
- databases are maintained by sqlserver
DATA TYPES IN SQL SERVER
INTEGER tiny int—1 small int-2 int—4 big—8
Float decimal(precision,scale)-5-17,float(p)-p<25-4,small money 4,money-8
Character char(n) fixed length character—4000bytes,varchar(n) variablelengthchar—n>0 n<=4000
Nchar--4000
Nvarchar--4000
Text(n)-2gb
Ntext(n)—2 power 30 -1
Binary(n)-4000
Varbinary(n)—n>=14 n<4000
Image(n)-2 poer 31-1
Bit—true or false-1
Small date time-2 1st jan 1900 to 6th june 2069
Date time-4---1st jan 1753 to 31st dec9999
Other data types
Sqlvariant-store any type of data
Table-a table itself
Xml-xml document
Timestamp-within a table if we declare then no need to give value it will be updated by db.
<code>
create database newdb
sp_helpdb "newdb"
use newdb
sp_renamedb 'newdb', 'hai'
drop database newdb
select * from newtable
</code]
creating a table
create table tablename(column1 datatype(width),col2 datatype(width) constaint specification,col3 datatype(width)-------);
CREATE TABLE
[code]
create table newtabel1(sno int,sname varchar(10),s1 int)
primary key
create table newtabel1(sno int primary key,sname varchar(10),s1 int)
[/code]
Insert
1…..insert into newtable values( 1,'hai',21)
2….insert into newtable (sno,s1) values(12,2)
3…insert into newtable values( 2,'myname',null)
select
select */column1,colum2,col3--- /expression [alias] from tabel1 [alias],[table2 [alias]--- n] [where <condition1> [and/or/not <condition2>---n] [order by <column1> asc\desc, <column2> asc/desc---n] [group by <expression>] [having <condition>]
[code]
select * from newtable
select sno,s2 from newtable
select sno,s1,s2,s1+s2 total from newtable
relational opertors in sql
>,<,>=,<=,<>,=
In(val1,val2)
NotIn(val1,val2)
Between<lowerbound> and <upperbound>
Not between<lb> and <ub>
Is null
Is not null
Like<pattern matching>
Not like<pm>
select sno,s1,s2,s1+s2 total from newtable where s1>20
select sno,s1,s2,s1+s2 total from newtable where s1>20
and s2<13
s select sno,s1,s2,s1+s2 total from newtable where sname=’nan’
select sno,s1,s2,s1+s2 total from newtabel where sname=’nan’ or sname=’hai’ or sname=’l’
select sno,s1,s2,s1+s2 total from newtable where sname in(‘lal’,’nan’)
select sno,s1,s2,s1+s2 total from newtable where sname not in (‘hai’)
select sno,s1,s2,s1+s2 total from newtable where s1 between 20 and 40
Like pattern matching cannot be used for numerics
select sno,s1,s2,s1+s2 total from newtabel where sname like ‘a%’
select sno,s1,s2,s1+s2 total from newtable where s1 is null
select sno,s1,s2,s1+s2 total from newtable where s1 is not null;
select sno,s1,s2,s1+s2 total from order by sname
select sno,s1,s2,s1+s2 total from newtableorder by sname, desc
[/code]
ALTER
Alter table tablename add/modify/delete columnname datatype(width)
[code]
alter table newtable add s2 int
[/code]
alter table tablename delete column columnname
DELETE
Delete from tablename
Delete from table name where condition
UPDATE
Update <tablename> set <column>=value where condition
DROP
Drop table tablename
Creating a table by taking information from already created table
Create table tablename as select statement
Create table exe as select * from emp where ename=’an’
RENAME
Rename oldtable name to newtablename
<select statement>
Copying rows from one table to another table
Insert into tablename (colname,col2) from tabelname(col1,col2)
The source and destination tables have same datatype and width of the colunns
Constraints
1.primary key
2.Check
3. unique
4. notnull
5.default
6.foerign key
7.null
To add constraint for already created table
Alter table tablename add constraint constraintname constraintspecification(column)
Alter table emp add constraint pk_emp_eno primarykey(eno)
Alter table emp enable constraint pk_emp_eno
Alter table emp disable constraint pk_emp_eno
To drop comstraint
Drop constraint constraintname
Drop constraint pk_emp_en
UNIQUE
It allows null vales
Create table emp(eno int primarykey, name varchar(20),sal float unique)
Create table emp(eno int primarykey, name varchar(20),check(sex in(‘m’,’f’,’M’,F’))
Create table emp(eno int primarykey, name varchar(20),age int check age between(18 to 50)
Notnull
Notnull with unique is equal to primary key
Create table emp(eno int primarykey, name varchar(20),age int notnull)
DEFAULT
Create table emp(eno int primarykey, name varchar(20),age int,town varchar(23) default ‘tirupati’)
-----------------THE END------------------
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