oracle sql

Anar Godjaevhttp://anargodjaev.wordpress.com/

Oracle SQL

Select lastname || ‘ is a ’ job_id as “employee details” from employees;

Select lastname from employees where lastname like ‘_0%’

Select employee_id , lastname, job_id from employeeswhere job_id like ‘%SAL%’ESCAPE’\_’;

Character functions:

Case manupilation

Lower Upper Initcap

Character manipulation

Concat (a,b) Substr (a,m,n) //same as mid function Length (a) İnstr (a,b,m,n) //instr(‘Hello World’ , ‘w’) Lpad (salary, 10, *) //(*****24000) Rpad Trim Replace (text, search, replace)

Number functions:

Round //rounds value to the specified decimal Round (45.926, 2) -> 45.93Trunc //truncates to the specified decimal Trunc (45.926,2) -> 45.92Mod //return the remainder of the division

Dates:

Date + number = dateDate – number =dateDate – date = number of days

http://anargodjaev.wordpress.com/


Select sysdate from dual; -- Default format DD-MON-RR

Months_between (date1, date2)Add_months (date,n)Next_day (date, ‘friday’) -- find the next specified day of the weekLast_day (date) -- the date of the last day of the monthRound (date)Trunc (date)

EX:

Round (sysdate, ‘MONTH’)Round (sysdate, ‘YEAR’)Trunc (sysdate, ‘MONTH’)Trunc (sysdate, ‘YEAR’)

Select employee_id , concat(fisrt_name, last_name) name, length (lastname) ,instr(lastname, ‘a’) “contains ‘a’ ?” from employees where substr(lastname,-1,1) = ‘n’;

to_char (number | date, [fmt])to_number (char, [fmt])to_date (char, [fmt])

alter session set nls_date_format = ‘DD-MM-YYY HH24:MI:SS’alter session set time_zone = ‘-8:00’

select sessiontimezone, dbtimezone, current_timestamp, current_date, sysdate from dual;

select extract (month from hire_date) from employees;select to_timestamp(‘2000-12-01 11:00:00’ , ‘YYYY-MM-DD HH:MI:SS’)

Select employee_id , to_char (hire_date, ‘MM/YY’) from employeeswhere last_name = ‘higgins’;// (YYYY,YEAR, MM, MONTH, MON, DAY, DD, DY, J)(HH24, MI, SS)



select to_char (hire_Date, ‘fmDD Month YYYY‘);select to_char (hire_date, ‘fmDdspth “of” month YYYY fmHH:MI:SS AM’)select last_name, hire_date from employeeswhere hire_Date = TO_DATE(‘May 24, 1999’, ‘fxMonth DD, YYYY’)

select to_char (salary, ‘$99,999.00’) 9 – represents a number 0 – forces a zero to be displayed $ - forces a floating ddler sign . – prints a decimal point , - prints a thousand indicator

nvl (expr1, expr2)nvl2 (expr1, expr2, expr3)nullif (expr1, expr2)coalesce (expr1, expr2, ... , exprn)

case expr when comparison1 then expr1 when comparison2 then expr2 else expr3end; alias

decode (col | expr, search1, result1, serach2, result2, default) alias;

decode (job_id , ‘IT_PROG’ , 1.10*SAL ‘SL_CLECK’, 1.15*SAL SAL) “REVISED_SAL”;

Joins:Select table1.column, table2.column from table1 , table2 where table1.column(+)=table2.column;

select table1.column, table2.column from table1 [CROSS join table2] [NATURAL join table2] [JOIN table2 USING column_name]

[JOIN table2 ON tbl1.column=tbl2.column] [LEFT | RIGHT | FULL OUTER join table2 ON tbl1.column ) tbl2.column]



SQLPLUS

define employee_id = 200;

set verify onset echo onshow echoset heading off | onshow headingshow _variable_nameset arraysize 20set feedback on | offset ttitle on | off | textset btitle on | off | textset break on | off | text | column

column lastname justify left format $99,990.00column lastname clear

col colname format a30

break on job_idnoprintbreak [on report element]clearscript file

printnull textcolumn colname option

Ex:set feedback offttitle ‘employee | report’ --top title [text | on | off]btitle ‘confidential’ --bottom titlebreak on job_idcolumn job_id heading ‘job / category’column lat_name heading ‘employee’column salary heading ‘salary’ format $99,999.99REM ** insert select statement

Select job_id , last_name salary from employees where salary < 15000Order by job_id, last_name;/

REM ** clear all formatting commands

Set feedback on



Column job_id clearColumn last_name clearColumn salary clearClear break

Merge into:Merge into table_name table_aliasUsing (table) aliasOn (join condition)When matched then update set col1 = val1 , col2 = val2When not matched then insert (col_list) values (val_list)

EX:Merge into copy_emp c using employee eon (c.employee_id = e.employee_id)When matched thenupdate set c.firstname = e.firstname ...when not matched theninsert values (e.emplyee_id ...)

Commit , rollback , savepoint:

Update ..Savepoint update_doneİnsertRollback to update_done

Create table dept80 as select * from employees where department_id = 80;

Alter table table_name add (column_name datatype)Alter table set unused column col_nameAlter table table_name modify (col_name datatype)

Alter table table_name drop (col_name)

Rename dept to dept_detail;Truncate table detail_dept;Select row_num as rank;


oracle sql

Technology