Dynmic Sorting Based SQL Query

select
 employee_number EMPNO,
 full_name NAME
from per_people_f
order by
  decode(:P2_ORDER_BY,'EMPNO',empno,null)
, decode(:P2_ORDER_BY,'NAME',name,null)
, decode(:P2_ORDER_BY,'EMPNO,FULL_NAME',empno,
 name,null)

UTL_FILE

While UTL_FILE.FCOPY can be used to copy valid text files, it does not copy binary files or invalid text files.  An example of an invalid text file would be one that contains a character sequence that cannot be generated by the characters on your keyboard (i.e. the sequence of two CR s in a row on a Windows platform rather than CRLF, CRLF) and hence may be considered a binary file.

NOTE: As UTL_FILE first supported the reading and writing of binary files in 10gR1, this note can only be used with Oracle Database versions 10gR1 and later.
Solution
Create two directory objects for the IN and OUT file locations.
CREATE OR REPLACE DIRECTORY in_file_loc AS 'C:\temp\in';
CREATE OR REPLACE DIRECTORY out_file_loc AS 'C:\temp\out';

NOTE: You must have the CREATE ANY DIRECTORY privilege to execute these statements.

Create the procedure CopyFile.
-- Procedure to COPY a Text or Binary file

CREATE OR REPLACE PROCEDURE copyfile (
   in_filename                IN             VARCHAR2
 , out_filename               IN             VARCHAR2
)
IS
   in_file                                           UTL_FILE.file_type;
   out_file                                          UTL_FILE.file_type;
   buffer_size                              CONSTANT INTEGER := 32767;   -- Max Buffer Size = 32767
   buffer                                            RAW (32767);
   buffer_length                                     INTEGER;
BEGIN
   -- Open a handle to the location where you are going to read the Text or Binary file from
   -- NOTE: The 'rb' parameter means "read in byte mode" and is only available
   --       in the UTL_FILE package with Oracle 10g or later
   in_file                                                  :=
                                                              UTL_FILE.fopen ('IN_FILE_LOC', in_filename, 'rb', buffer_size);
   -- Open a handle to the location where you are going to write the Text or Binary file to
   -- NOTE: The 'wb' parameter means "write in byte mode" and is only available
   --       in the UTL_FILE package with Oracle 10g or later
   out_file                                                 :=
                                                            UTL_FILE.fopen ('OUT_FILE_LOC', out_filename, 'wb', buffer_size);
   -- Attempt to read the first chunk of the in_file
   UTL_FILE.get_raw (in_file, buffer, buffer_size);
   -- Determine the size of the first chunk read
   buffer_length                                            := UTL_RAW.LENGTH (buffer);

   -- Only write the chunk to the out_file if data exists
   WHILE buffer_length > 0
   LOOP
      -- Write one chunk of data
      UTL_FILE.put_raw (out_file, buffer, TRUE);

      -- Read the next chunk of data
      IF buffer_length = buffer_size
      THEN
         -- Buffer was full on last read, read another chunk
         UTL_FILE.get_raw (in_file, buffer, buffer_size);
         -- Determine the size of the current chunk
         buffer_length                                            := UTL_RAW.LENGTH (buffer);
      ELSE
         buffer_length                                            := 0;
      END IF;
   END LOOP;

   -- Close the file handles
   UTL_FILE.fclose (in_file);
   UTL_FILE.fclose (out_file);
EXCEPTION
   -- Raised when the size of the file is a multiple of the buffer_size
   WHEN NO_DATA_FOUND
   THEN
      -- Close the file handles
      UTL_FILE.fclose (in_file);
      UTL_FILE.fclose (out_file);
END;
/

Test procedure CopyFile with both Text and Binary files.

-- Test a TEXT file
EXEC CopyFile('original_textfilename.txt', 'new_textfilename.txt')

-- Test a BINARY File
EXEC CopyFile('original_binaryfilename.jpg', 'new_binaryfilename.jpg')

Check the IN_FILE_LOC and OUT_FILE_LOC and verify that the files were successfully copied.  Compare the actual size in bytes to make sure they are an exact copy. 

UTILFILE-INBOUND,OUTBOUND

=================== UTL FILE INBOUND===
USING UTL_FILE PACKAGE(LOAD THE DATA IN TO THE TABLE)
CREATE OR REPLACE package body APPS.xx_po_pu_det_pkg
is
/*
Procedure to read data from flat file
*/
    procedure pur_dat_prc(x_errbuf OUT VARCHAR2
                        ,X_RETCODE OUT VARCHAR2
                        ,P_FILE_PATH IN VARCHAR2
                        ,P_FIL_NAME IN VARCHAR2
                        )
is

v_file_type         utl_file.file_type;
v_data              varchar2(1000);

v_vendor_number         po_vendors.segment1%type;
v_vendor_name           po_vendors.vendor_name%type;
v_vendor_site_code      po_vendor_sites_all.vendor_site_code%type;
v_po_number             po_headers_all.segment1%type;

begin
    v_file_type := utl_file.fopen(P_FILE_PATH,P_FIL_NAME,'R');
    loop
        begin
 --       fnd_file.put_line(fnd_file.output,'Start Loop');
        utl_file.get_line(v_file_type,v_data);
        fnd_file.put_line(fnd_file.output,'Data => '||v_data);
    select substr(v_data,1,instr(v_data,',',1)-1)
    into v_vendor_number
    from dual;
   
    select substr(v_data,instr(v_data,',',1,1)+1,instr(v_data,',',1,2)-(instr(v_data,',',1,1)+1))
    into v_vendor_name
    from dual;

    select substr(v_data,instr(v_data,',',1,2)+1,instr(v_data,',',1,3)-(instr(v_data,',',1,2)+1))
    into v_vendor_site_code
    from dual;

    select substr(v_data,instr(v_data,',',1,3)+1,length(v_data)-(instr(v_data,',',1,3)))
    into v_po_number
    from dual;

    insert into XX_PO_PUR_DET_STG
    values(
    v_vendor_number
    ,v_vendor_name
    ,v_vendor_site_code
    ,v_po_number
    );
   
    exception
        when utl_file.invalid_path then
            fnd_file.put_line(fnd_file.output,'Invalid file path');      
        when utl_file.invalid_mode then
            fnd_file.put_line(fnd_file.output,'Invalid Mode');
        when utl_file.invalid_filehandle then
            fnd_file.put_line(fnd_file.output,'Invalid file handle');
        when utl_file.invalid_operation then
            fnd_file.put_line(fnd_file.output,'Invalid file operation');
        when utl_file.read_error then
            fnd_file.put_line(fnd_file.output,'Read error');
        when no_data_found then
            exit;
        when others then
           fnd_file.put_line(fnd_file.output,'Others exception => '||SQLERRM);    
        end;
    end loop;
--    fnd_file.put_line(fnd_file.output,'after end loop');
    utl_file.fclose(v_file_type);
--    fnd_file.put_line(fnd_file.output,'after close');
exception
    when others then
        fnd_file.put_line(fnd_file.log,'Exception in procedure pur_dat_prc => '||SQLERRM);
end pur_dat_prc;          
end xx_po_pu_det_pkg;
/



===================UTIL FILE OUT BOUND==============
USING UTL_FILE PACKAGE (OUT BOUND)
CREATE OR REPLACE procedure
APPS.xx_po_out(x_errbuf out varchar2
,p_retcode out varchar2
,p_file_path in varchar2
,p_file_name in varchar2
)
is
g_org_id number := fnd_profile.value('ORG_ID');
g_conc_request_id number := fnd_profile.value('CONC_REQUEST_ID');
cursor cur_podet
is
select vendor_name
,pov.segment1 vendor_number
,povs.VENDOR_SITE_CODE
,povs.ADDRESS_LINE1||' '||povs.ADDRESS_LINE2 address
,povs.country
,poh.SEGMENT1 po_number
from po_vendors pov,
po_headers_all poh,
po_vendor_sites_all povs
where pov.vendor_id = poh.vendor_id
and poh.vendor_site_id = povs.vendor_site_id
and poh.org_id = g_org_id;

v_file utl_file.file_type;
v_file_name varchar2(100) ;


begin
    fnd_file.put_line(fnd_file.log,'Concurrent Request Id => '||p_file_name||'_'||g_conc_request_id||'.txt');
    v_file_name  := p_file_name||'_'||g_conc_request_id||'.txt';
    v_file := utl_file.fopen(p_file_path,v_file_name ,'W');
    for rec_podet in cur_podet
    loop
        begin
        utl_file.PUT_LINE(v_file,
         rec_podet.vendor_name
        ||','||rec_podet.vendor_number
        ||','||rec_podet.VENDOR_SITE_CODE
        ||','||rec_podet.address
        ||','||rec_podet.country
        ||','||rec_podet.po_number
        );
    exception
        when utl_file.invalid_path then
            fnd_file.put_line(fnd_file.log,'Invalid Path');
        when utl_file.invalid_mode  then
            fnd_file.put_line(fnd_file.log,'Invalid Mode');
        when utl_file.invalid_filehandle then
            fnd_file.put_line(fnd_file.log,'Invalid file handle');
        when utl_file.invalid_operation  then
            fnd_file.put_line(fnd_file.log,'Invalid Operation');
        when utl_file.write_error        then
            fnd_file.put_line(fnd_file.log,'Write error');
        when others then
            fnd_file.put_line(fnd_file.log,'exception in loop => '||SQLERRM);
        end;  
    end loop;
    utl_file.FCLOSE(v_file);
exception
    when others then
        fnd_file.put_line(fnd_file.log,'exception in procedure => '||SQLERRM);  
end ;

SQL-MULTIPLE INSERTS

MULTIPLE INSERTS

We have table called DEPT with the following columns and data

DEPTNO         DNAME           LOC
--------            --------            ----
10                    accounting    new york
20                    research        dallas
30                    sales               Chicago
40                    operations    boston

a) CREATE STUDENT TABLE

     SQL> Create table student(no number(2),name varchar(2),marks number(3));

b) MULTI INSERT WITH ALL FIELDS

     SQL> Insert all
             Into student values(1,’a’,100)
             Into student values(2,’b’,200)
             Into student values(3,’c’,300)
             Select *from dept where deptno=10;

     -- This inserts 3 rows

c) MULTI INSERT WITH SPECIFIED FIELDS

     SQL> insert all
             Into student (no,name) values(4,’d’)
             Into student(name,marks) values(’e’,400)
             Into student values(3,’c’,300)
             Select *from dept where deptno=10;

     -- This inserts 3 rows

d) MULTI INSERT WITH DUPLICATE ROWS

     SQL> insert all
             Into student values(1,’a’,100)
             Into student values(2,’b’,200)
             Into student values(3,’c’,300)
             Select *from dept where deptno > 10;

     -- This inserts 9 rows because in the select statement retrieves 3 records (3 inserts for
         each row retrieved)

e) MULTI INSERT WITH CONDITIONS BASED

     SQL> Insert all
             When deptno > 10 then
             Into student1 values(1,’a’,100)
             When dname = ‘SALES’ then
             Into student2 values(2,’b’,200)
             When loc = ‘NEW YORK’ then
             Into student3 values(3,’c’,300)
             Select *from dept where deptno>10;

     -- This  inserts 4 rows because the first condition satisfied 3 times, second condition
         satisfied once and the last none.

f) MULTI INSERT WITH CONDITIONS BASED AND ELSE

    SQL> Insert all
            When deptno > 100 then
            Into student1 values(1,’a’,100)
            When dname = ‘S’ then
            Into student2 values(2,’b’,200)
            When loc = ‘NEW YORK’ then
            Into student3 values(3,’c’,300)
            Else
            Into student values(4,’d’,400)
            Select *from dept where deptno>10;

     -- This inserts 3 records because the else satisfied 3 times

g) MULTI INSERT WITH CONDITIONS BASED AND FIRST

     SQL> Insert first
             When deptno = 20 then
             Into student1 values(1,’a’,100)
             When dname = ‘RESEARCH’ then
             Into student2 values(2,’b’,200)
             When loc = ‘NEW YORK’ then
             Into student3 values(3,’c’,300)
             Select *from dept where deptno=20;
   
     -- This inserts 1 record because the first clause avoid to check the remaining
         conditions once the condition is satisfied.

h) MULTI INSERT WITH CONDITIONS BASED, FIRST AND ELSE

     SQL> Insert first
             When deptno = 30 then
              Into student1 values(1,’a’,100)
              When dname = ‘R’ then
              Into student2 values(2,’b’,200)
              When loc = ‘NEW YORK’ then
              Into student3 values(3,’c’,300)
              Else
              Into student values(4,’d’,400)
              Select *from dept where deptno=20;

     -- This inserts 1 record because the else clause satisfied once




i) MULTI INSERT WITH MULTIBLE TABLES

    SQL> Insert all
            Into student1 values(1,’a’,100)
            Into student2 values(2,’b’,200)
            Into student3 values(3,’c’,300)
            Select *from dept where deptno=10;

    -- This inserts 3 rows

    ** You can use multi tables with specified fields, with duplicate rows, with conditions,
         with first and else clauses.

SQL-FUNCTIONS1(DATE FUNCTIONS)

DATE FUNCTIONS

  Sysdate
  Current_date
  Current_timestamp
  Systimestamp
  Localtimestamp
  Dbtimezone
  Sessiontimezone
  To_char
  To_date
  Add_months
  Months_between
  Next_day
  Last_day
  Extract
  Greatest
  Least
  Round
  Trunc
  New_time
 Coalesce

Oracle default date format is DD-MON-YY.
We can change the default format to our desired format by using the following command.

SQL> alter session set nls_date_format = ‘DD-MONTH-YYYY’;
        But this will expire once the session was closed.

a) SYSDATE

     This will give the current date and time.
      Ex:
           SQL> select sysdate from dual;

SYSDATE
-----------
24-DEC-06

b) CURRENT_DATE

     This will returns the current date in the session’s timezone.

      Ex:
           SQL> select current_date from dual;

CURRENT_DATE
------------------
     24-DEC-06

c) CURRENT_TIMESTAMP

     This will returns the current timestamp with the active time zone information.

      Ex:
           SQL> select current_timestamp from dual;

CURRENT_TIMESTAMP
---------------------------------------------------------------------------
24-DEC-06 03.42.41.383369 AM +05:30


d) SYSTIMESTAMP

     This will returns the system date, including fractional seconds and time zone of the
      database.

      Ex:
           SQL> select systimestamp from dual;
SYSTIMESTAMP
---------------------------------------------------------------------------
24-DEC-06 03.49.31.830099 AM +05:30

e) LOCALTIMESTAMP

     This will returns local timestamp in the active time zone information, with no time
     zone information shown.

      Ex:
                   SQL> select localtimestamp from dual;

LOCALTIMESTAMP
---------------------------------------------------------------------------
24-DEC-06 03.44.18.502874 AM


f) DBTIMEZONE

    This will returns the current database time zone in UTC format. (Coordinated Universal
    Time)

    Ex:
                   SQL> select dbtimezone from dual;

DBTIMEZONE
---------------
   -07:00

g) SESSIONTIMEZONE

    This will returns the value of the current session’s time zone.

    Ex:
         SQL> select sessiontimezone from dual;

SESSIONTIMEZONE
------------------------------------
+05:30

     
       h) TO_CHAR

    This will be used to extract various date formats.
    The available date formats as follows.

    Syntax: to_char (date, format)
 
    DATE FORMATS
 
            D                      --         No of days in week
            DD                    --         No of days in month
            DDD                 --         No of days in year
            MM                   --         No of month
            MON                 --         Three letter abbreviation of month
            MONTH             --         Fully spelled out month
            RM                   --         Roman numeral month
            DY                    --         Three letter abbreviated day
            DAY                  --         Fully spelled out day
            Y                      --         Last one digit of the year
            YY                    --         Last two digits of the year
            YYY                  --         Last three digits of the year
            YYYY                --         Full four digit year
            SYYYY             --          Signed year
            I                       --         One digit year from ISO standard
            IY                     --         Two digit year from ISO standard
            IYY                   --         Three digit year from ISO standard
            IYYY                 --         Four digit year from ISO standard
            Y, YYY              --         Year with comma
            YEAR                --         Fully spelled out year
            CC                    --         Century
            Q                      --         No of quarters
            W                     --         No of weeks in month
            WW                  --         No of weeks in year
            IW                    --         No of weeks in year from ISO standard
            HH                    --         Hours
            MI                    --         Minutes
            SS                    --         Seconds
            FF                     --         Fractional seconds
            AM or PM         --         Displays AM or PM depending upon time of day
            A.M or P.M       --         Displays A.M or P.M depending upon time of day
            AD or BC          --         Displays AD or BC depending upon the date
            A.D or B.C        --         Displays AD or BC depending upon the date
            FM                    --         Prefix to month or day, suppresses padding of month or day
            TH                    --         Suffix to a number
            SP                    --         suffix to a number to be spelled out
            SPTH                --         Suffix combination of TH and SP to be both spelled out
            THSP                --         same as SPTH

Ex:
    SQL> select to_char(sysdate,'dd month yyyy hh:mi:ss am dy') from dual;

TO_CHAR(SYSDATE,'DD MONTH YYYYHH:MI
----------------------------------------------------
24 december  2006 02:03:23 pm sun  

    SQL> select to_char(sysdate,'dd month year') from dual;


TO_CHAR(SYSDATE,'DDMONTHYEAR')
-------------------------------------------------------
24 december  two thousand six

     SQL> select to_char(sysdate,'dd fmmonth year') from dual;

TO_CHAR(SYSDATE,'DD FMMONTH YEAR')
-------------------------------------------------------
24 december two thousand six

     SQL> select to_char(sysdate,'ddth DDTH') from dual;

TO_CHAR(S
------------
24th 24TH

     SQL> select to_char(sysdate,'ddspth DDSPTH') from dual;

TO_CHAR(SYSDATE,'DDSPTHDDSPTH
------------------------------------------
twenty-fourth TWENTY-FOURTH

     SQL> select to_char(sysdate,'ddsp Ddsp DDSP ') from dual;

TO_CHAR(SYSDATE,'DDSPDDSPDDSP')
------------------------------------------------
twenty-four Twenty-Four TWENTY-FOUR

i) TO_DATE

    This will be used to convert the string into data format.

    Syntax: to_date (date)

    Ex:
         SQL> select to_char(to_date('24/dec/2006','dd/mon/yyyy'), 'dd * month * day')
                 from dual;

TO_CHAR(TO_DATE('24/DEC/20
--------------------------
24 * december  * Sunday

-- If you are not using to_char oracle will display output in default date format.
     
j) ADD_MONTHS

    This will add the specified months to the given date.

    Syntax: add_months (date, no_of_months)

    Ex:
          SQL> select add_months(to_date('11-jan-1990','dd-mon-yyyy'), 5) from dual;

ADD_MONTHS
----------------
11-JUN-90

SQL> select add_months(to_date('11-jan-1990','dd-mon-yyyy'), -5) from dual;

ADD_MONTH
---------------
11-AUG-89        

Ø  If no_of_months is zero then it will display the same date.
Ø  If no_of_months is null then it will display nothing.

k) MONTHS_BETWEEN

    This will give difference of months between two dates.

    Syntax: months_between (date1, date2)

    Ex:
         SQL> select months_between(to_date('11-aug-1990','dd-mon-yyyy'), to_date('11-
                 jan-1990','dd-mon-yyyy')) from dual;



MONTHS_BETWEEN(TO_DATE('11-AUG-1990','DD-MON-YYYY'),TO_DATE('11-JAN-1990','DD-MON-YYYY'))
-----------------------------------------------------------------------------------------------
                                                                                        7
           SQL> select months_between(to_date('11-jan-1990','dd-mon-yyyy'), to_date('11-
                 aug-1990','dd-mon-yyyy')) from dual;

MONTHS_BETWEEN(TO_DATE('11-JAN-1990','DD-MON-YYYY'),TO_DATE('11-AUG-1990','DD-MON-YYYY'))
-------------------------------------------------------------------------------------------------
                                                                                       -7

l) NEXT_DAY
               
    This will produce next day of the given day from the specified date.

    Syntax: next_day (date,  day)

    Ex:
         SQL> select next_day(to_date('24-dec-2006','dd-mon-yyyy'),'sun') from dual;

NEXT_DAY(
-------------
31-DEC-06

-- If the day parameter is null then it will display nothing.

m) LAST_DAY

    This will produce last day of the given date.

    Syntax: last_day (date)

    Ex:
         SQL> select last_day(to_date('24-dec-2006','dd-mon-yyyy'),'sun') from dual;
LAST_DAY(
-------------
31-DEC-06

n) EXTRACT

    This is used to extract a portion of the date value.

    Syntax: extract ((year | month | day | hour | minute | second), date)

    Ex:
         SQL> select extract(year from sysdate) from dual;
EXTRACT(YEARFROMSYSDATE)
------------------------------------
                    2006

-- You can extract only one value at a time.

o) GREATEST

     This will give the greatest date.

     Syntax: greatest (date1, date2, date3 … daten)

     Ex:
         SQL> select greatest(to_date('11-jan-90','dd-mon-yy'),to_date('11-mar-90','dd-
                 mon-yy'),to_date('11-apr-90','dd-mon-yy')) from dual;

  GREATEST(
  -------------
   11-APR-90

p) LEAST

     This will give the least date.
     Syntax: least (date1, date2, date3 … daten)

     Ex:
         SQL> select least(to_date('11-jan-90','dd-mon-yy'),to_date('11-mar-90','dd-mon-
                 yy'),to_date('11-apr-90','dd-mon-yy')) from dual;

  LEAST(
  -------------
   11-JAN-90

q) ROUND

    Round will rounds the date to which it was equal to or greater than the given date.

    Syntax: round (date, (day | month | year))

    If the second parameter was year then round will checks the month of the given date in
    the following ranges.

JAN      --          JUN  
            JUL       --          DEC

    If the month falls between JAN and JUN then it returns the first day of the current year.
    If the month falls between JUL and DEC then it returns the first day of the next year.

    If the second parameter was month then round will checks the day of the given date in
    the following ranges.

            1          --         15    
            16        --         31

    If the day falls between 1 and 15 then it returns the first day of the current month.
    If the day falls between 16 and 31 then it returns the first day of the next month.

    If the second parameter was day then round will checks the week day of the given date
    in the following ranges.

            SUN      --          WED
            THU      --          SUN

    If the week day falls between SUN and WED then it returns the previous sunday.
    If the weekday falls between THU and SUN then it returns the next sunday.

Ø  If the second parameter was null then it returns nothing.
Ø  If the you are not specifying the second parameter then round will resets the time to the begining of the current day in case of user specified date.
Ø  If the you are not specifying the second parameter then round will resets the time to the begining of the next day in case of sysdate.

    Ex:
         SQL> select round(to_date('24-dec-04','dd-mon-yy'),'year'), round(to_date('11-mar-
                 06','dd-mon-yy'),'year') from dual;

ROUND(TO_ ROUND(TO_
------------   ---------------
01-JAN-05   01-JAN-06

           SQL> select round(to_date('11-jan-04','dd-mon-yy'),'month'), round(to_date('18-
                 jan-04','dd-mon-yy'),'month') from dual;

ROUND(TO_ ROUND(TO_
-------------  ---------------
01-JAN-04    01-FEB-04

           SQL> select round(to_date('26-dec-06','dd-mon-yy'),'day'), round(to_date('29-dec-
                 06','dd-mon-yy'),'day') from dual;

ROUND(TO_ ROUND(TO_
--------------  --------------
24-DEC-06     31-DEC-06

           SQL> select to_char(round(to_date('24-dec-06','dd-mon-yy')), 'dd mon yyyy
                 hh:mi:ss am') from dual;
TO_CHAR(ROUND(TO_DATE('
---------------------------------
24 dec 2006 12:00:00 am
r) TRUNC

    Trunc will chops off the date to which it was equal to or less than the given date.

    Syntax: trunc (date, (day | month | year))

  If the second parameter was year then it always returns the first day of the current year.
  If the second parameter was month then it always returns the first day of the current month.
  If the second parameter was day then it always returns the previous sunday.
  If the second parameter was null then it returns nothing.
  If the you are not specifying the second parameter then trunk will resets the time to the begining of the current day.

    Ex:
         SQL> select trunc(to_date('24-dec-04','dd-mon-yy'),'year'), trunc(to_date('11-mar-
                 06','dd-mon-yy'),'year') from dual;

TRUNC(TO_ TRUNC(TO_
-------------  --------------
01-JAN-04    01-JAN-06

                     SQL> select trunc(to_date('11-jan-04','dd-mon-yy'),'month'), trunc(to_date('18-jan-
                         04','dd-mon-yy'),'month') from dual;

TRUNC(TO_ TRUNC(TO_
-------------  -------------
01-JAN-04    01-JAN-04

  SQL> select trunc(to_date('26-dec-06','dd-mon-yy'),'day'), trunc(to_date('29-dec-
          06','dd-mon-yy'),'day') from dual;
                        TRUNC(TO_ TRUNC(TO_
-------------  --------------
24-DEC-06 24-DEC-06
       
          SQL> select to_char(trunc(to_date('24-dec-06','dd-mon-yy')), 'dd mon yyyy hh:mi:ss
                 am') from dual;

TO_CHAR(TRUNC(TO_DATE('
---------------------------------
24 dec 2006 12:00:00 am

s) NEW_TIME

     This will give the desired timezone’s date and time.

     Syntax: new_time (date, current_timezone, desired_timezone)

     Available timezones are as follows.

    TIMEZONES

                        AST/ADT         --         Atlantic standard/day light time
                        BST/BDT          --         Bering standard/day light time
                        CST/CDT          --         Central standard/day light time
                        EST/EDT          --         Eastern standard/day light time
                        GMT                --         Greenwich mean time
                        HST/HDT         --         Alaska-Hawaii standard/day light time
                        MST/MDT         --         Mountain standard/day light time
                        NST                 --          Newfoundland standard time
                        PST/PDT          --         Pacific standard/day light time
                        YST/YDT          --         Yukon standard/day light time

    Ex:
        SQL> select to_char(new_time(sysdate,'gmt','yst'),'dd mon yyyy hh:mi:ss am') from
                dual;

TO_CHAR(NEW_TIME(SYSDAT
-----------------------------------
24 dec 2006 02:51:20 pm

          SQL> select to_char(new_time(sysdate,'gmt','est'),'dd mon yyyy hh:mi:ss am') from
                dual;

TO_CHAR(NEW_TIME(SYSDAT
-----------------------
24 dec 2006 06:51:26 pm

t) COALESCE

    This will give the first non-null date.

    Syntax: coalesce (date1, date2, date3 … daten)

    Ex:
         SQL> select coalesce('12-jan-90','13-jan-99'), coalesce(null,'12-jan-90','23-mar-
                 98',null) from dual;

COALESCE( COALESCE(
-------------  ------------
12-jan-90     12-jan-90