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Python Database Connectivity1|Manohar Papasani
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Database
---------------
Collection of tables
Table is collection of cols
col is a field.
creating a database
-------------------
create database databasename
ex:
create database test
Example
-------
MySql
Oracle
sql server
sybase
DB2
..
..
sql
---
DDl---create
Alter
drop
DML--insert
update
delete
select
creating a table
----------------
create
sytax
-----
create table tablename(col1 datatype,col2 datatype,....);
ex:
employee
eno--int
ename--varchar
sal--double
displaying schema of table
--------------------------
desc tablename;
insert
------
syntax
------
insert into tablename values(value1,value2,.....);
ex:
insert into employee values(1,'manohar',20000.00);
selecting data from a table
---------------------------
select
syntax
------
select *from tablename;
ex:
select *from employee;
seleting a specific row
-----------------------
select *from employee where enoo=1;
selecting partial row
---------------------
select eno,name from employee;
updating a table
----------------
syntax
------
update tablename set col1=value,col2=value,... where condition;
ex:
update employee set sal=50000.00 where eno=1;
delete
------
delete a row,or rows from a table.
deleting all rows from a table
syntax
------
delete from employee;
deleting a specific row
syntax
------
delete from employee where condition;
---------------
Collection of tables
Table is collection of cols
col is a field.
creating a database
-------------------
create database databasename
ex:
create database test
Example
-------
MySql
Oracle
sql server
sybase
DB2
..
..
sql
---
DDl---create
Alter
drop
DML--insert
update
delete
select
creating a table
----------------
create
sytax
-----
create table tablename(col1 datatype,col2 datatype,....);
ex:
employee
eno--int
ename--varchar
sal--double
displaying schema of table
--------------------------
desc tablename;
insert
------
syntax
------
insert into tablename values(value1,value2,.....);
ex:
insert into employee values(1,'manohar',20000.00);
selecting data from a table
---------------------------
select
syntax
------
select *from tablename;
ex:
select *from employee;
seleting a specific row
-----------------------
select *from employee where enoo=1;
selecting partial row
---------------------
select eno,name from employee;
updating a table
----------------
syntax
------
update tablename set col1=value,col2=value,... where condition;
ex:
update employee set sal=50000.00 where eno=1;
delete
------
delete a row,or rows from a table.
deleting all rows from a table
syntax
------
delete from employee;
deleting a specific row
syntax
------
delete from employee where condition;