explain to_char

Similar Questions

• Explain the (), TO_DATE (), () with examples TO_NUMBER TO_CHAR

  Hi all

  I little bit on (), TO_DATE (), () TO_NUMBER TO_CHAR confusion.

  Can you please explain when to use which works with examples.

  Thank you and best regards,

  Format patterns

• explain DBMS_APPLICATION_INFO

  Hi all

  In the package in the Begin block

  BEGIN

  DBMS_APPLICATION_INFO. SET_MODULE ( module_name = > 'PKG', )

  action_name = > 'proc1-opening slider');

  FOR... LOOP

  BEGIN

  DBMS_APPLICATION_INFO. SET_ACTION (' proc1 :'||) To_char (v_count) | "done");

  v_count: = v_count + 1;

  END;

  END LOOP;

  END;

  can you please explain about it?

  Thank you

  N ° action is a description of real processing step.

  For example the module is called billing and action is Application of discount.

  Put an arbitrary number as action is ridiculous - it has no meaning.

  If you know the number of cycles treatment there is (e.g. lines how many process), you can create a long operation - who to see and interpret correctly monitoring/admin tools.

• To_char - NUMBER (5) - beginning and ending zeros

  I'm reviewing the code and came across: RPAD (LPAD (TO_CHAR (col), 9, '0'), 11, '0') where the neck is NUMBER (5, 0) NOT NULL default 0 value.

  FWIW (in QA): SELECT LENGTH (col), SIGN (col), COUNT (*) C to tab GROUP BY LENGTH (col), SIGN (col) ORDER BY 1.2;

  22196 0 1

  1 1 5746

  2 1 53553

  3 1 410260

  4-1 16

  4 1 23198

  5-1-25

  The output sample I does not contain any negative numbers. Apparently, it is excluded from the query with a different logic (although not directly) or these data are only test cases.

  The intention seems to be to add up to 8 zeros and 2 zeros. A function pad seems redundant as TO_CHAR itself can do the job, although it does not appear that TO_CHAR can add two zeros in the same call start and end. Given that the latter is only two zeros, I just say concatenate is better: TO_CHAR (col, 'FM000000009'). '00'. technically, this is not the same as the current expression, that when the number is negative, the sign is placed in the middle of the string! I guess that it is not expected that the case should not. Maybe I can 'fix' and leave a comment explaining the original behavior.

  Is it possible to add the preceding and zeros with a function of leak?

  Post edited by: Brian Tkatch Put the bracket in the right place. Oops!

  Hello

  Sorry, it is not clear what you want.

  Whenver you have questions, post a small example data (CREATE TABLE and only relevant columns, INSERT statements) and also post the results desired from these data.

  Explain, using specific examples, how you get these results from these data.

  Always say what version of Oracle you are using (for example, 11.2.0.2.0).

  See the FAQ forum: https://forums.oracle.com/message/9362002

  Why do you need a single function?  Why not something like

  To_char (col, '000000000') | '00'

  ?

  If you must do so within a single function:

  To_char (col, '000000000V99') - V99 adds 2 0 leak

  The comment is necessary, because someone who has to maintain the code (including you in a few months) knows what V99 done and will lose time looking at a maximum.

• Strange TO_DATE/TO_CHAR

  Hi all

  I am facing a problem with To_char function for the date object.

  I am trying to execute the following SQL code:

  Select do_date, XXX, to_char (xxx))

  Select

  TO_DATE)

  case substr (do_date, 1, 14)

  When '2016' then do_date

  of another substr (do_date, 1, 14)

  end

  , 'YYYYMMDDhh24miss '.

  )

  XXX, wns_attack_meminfo_work do_date

  );

  The result is

  DO_DATE XXX TO_CHAR (XXX)

  -------------- ------------------------------- ------------

  20150731181234 31 JULY 15 000-00-00

  20150731181234 31 JULY 15 000-00-00

  20150731181234 31 JULY 15 000-00-00

  20150731181234 31 JULY 15 000-00-00

  Any body knows why, when XXX has a valid value, TO_CHAR (XXX) returns an incorrect value?

  I run the query against ORACLE 10 g 10.2.0.1.0, 32-bit, Windows server 2003.

  When I try to run the same query against an another DB (CENTOS5.5_64, 10.2.0.4.0, 64-bit) the result is ok.

  I not only have to solve this problem, but also need to explain to the client why we have this problem.

  Any help is highly appreciated.

  Thanks in advance,

  Tuan

  Simple guideline - if there is no other difference between the two databases and it works on 10.2.0.4 but not on 10.2.0.1 then there is a very good chance that you look at a bug that is corrected.

  In your case, the result is something that "cannot possibly" appears, this suggests a bug even more strongly; and then you can't help but notice that your SQL * Plus shows XXX as a readable date, she made an implicit conversion of some sort and you expect your Explicit to_char() (server side) to work as well.

  You dump (XXX) is very informative. Type 7 is what you get by immersion of a date of database column, type 8, that's what you get by dumping (e.g. SYSDATE) when it is used as a variable. This suggests an error in the internal code that produces a gap between two stages of execution of SQL.

  Speculation is not necessary, though - I just did a quick search on Metalink (MOS) in the "Bug" database for 'to_date' "" 000-00-00 and found the following: Bug 5174854 : RETURNS TO_CHAR ON A DATE VALUE "000-00-00 '.

  Reported in 10.2.0.1, 10.2.0.2 fixed

  Concerning

  Jonathan Lewis

• Please explain this part of the code

  CREATE OR REPLACE PROCEDURE IS abc123
  -Statements
  v_T_MAP_record T_MAP_map % ROWTYPE;
  
  TYPE t_element_cursor IS REF CURSOR;
  v_T_MAP_cursor t_element_cursor;
  
  number of v_T_MAP_count;
  BEGIN
  DBMS_OUTPUT. ENABLE (1000000);
  v_T_MAP_cursor: = get_T_MAPs (1308); -This will get the record of the cursor
  
  -Open the cursor
  EXTRACTION v_T_MAP_cursor
  IN v_T_MAP_record;
  
  V_T_MAP_cursor % FOUND LOOP
  
  dbms_output.put_line ('uc.use_case_id: ' | v_T_MAP_record.use_case_id);
  
  
  v_T_MAP_count: = v_T_MAP_count + 1;
  
  EXTRACTION v_T_MAP_cursor
  IN v_T_MAP_record;
  
  END LOOP;
  
  -Close the cursor
  CLOSE V_T_MAP_cursor;
  
  EXCEPTION
  While OTHERS THEN
  dbms_output.put_line ('Error' |) TO_CHAR (SQLCODE) | ': ' || SQLERRM);
  END;
  
  I do not understand why we are having 2 game instruction Fetch IN v_T_MAP_record's first before the while loop v_T_MAP_cursor and the other inside the v_T_MAP_cursor. Please explain. If I remove the second instruction fetch inside the loop, it gives me a buffer overflow error.

  It's what he does...

  CREATE OR REPLACE PROCEDURE abc123  IS
      --Variable declarations
      v_T_MAP_record T_MAP_map%ROWTYPE;
  
      TYPE t_element_cursor IS REF CURSOR;
      v_T_MAP_cursor t_element_cursor;
  
      v_T_MAP_count number;
    BEGIN
      DBMS_OUTPUT.ENABLE(1000000);  -- THIS ISN'T REALLY NEEDED
  
      -- This opens the ref cursor, it doesn't fetch anything (assuming get_T_MAPs doesn't fetch itself)
      v_T_MAP_cursor := get_T_MAPs(1308);
  
      -- This fetches the first record from the cursor
      FETCH v_T_MAP_cursor
        INTO v_T_MAP_record;
  
      -- If a record is found we enter a loop
      WHILE v_T_MAP_cursor%FOUND LOOP
        -- output the current record details
        dbms_output.put_line('uc.use_case_id: '||v_T_MAP_record.use_case_id);
        v_T_MAP_count := v_T_MAP_count + 1;
  
        -- fetch the next record
        FETCH v_T_MAP_cursor
          INTO v_T_MAP_record;
        -- loop back to the start of the while loop
      END LOOP;
  
      --Close the cursor
      CLOSE v_T_MAP_cursor;
  
    -- Pointless stupid exception handler
    EXCEPTION
      when OTHERS THEN
        dbms_output.put_line('Error ' || TO_CHAR(SQLCODE) || ': ' || SQLERRM);
    END;
  

  Although this would be a better style:

  CREATE OR REPLACE PROCEDURE abc123  IS
    --Variable declarations
    v_T_MAP_record T_MAP_map%ROWTYPE;
    TYPE t_element_cursor IS REF CURSOR;
    v_T_MAP_cursor t_element_cursor;
    v_T_MAP_count number;
  BEGIN
    -- This opens the ref cursor, it doesn't fetch anything (assuming get_T_MAPs doesn't fetch itself)
    v_T_MAP_cursor := get_T_MAPs(1308);
  
    LOOP
      -- This fetches the first/next record from the cursor
      FETCH v_T_MAP_cursor INTO v_T_MAP_record;
      EXIT WHEN v_T_MAP_cursor%NOTFOUND;
  
      dbms_output.put_line('uc.use_case_id: '||v_T_MAP_record.use_case_id);
      v_T_MAP_count := v_T_MAP_count + 1;
    END LOOP;
  
    --Close the cursor
    CLOSE v_T_MAP_cursor;
  END;
  

  However, I would also change things to use the SYS_REFCURSOR as the need to define your own type from the REF CURSOR was placed back in 9i with the new type built in SYS_REFCURSOR.
  There are probably many other things I would like examine why I'm using ref Cursor in the first place and why I try to write data using dbms_output etc., but hey, we all have start somewhere.

  Published by: BluShadow on 28-Sep-2012 14:28

• PLAN of EXPLAIN used

  Hello
  on 9i
  How can we find explain the plan already used for a query?
  Thank you.

  Yes, in 9i there is no sql_id. SQL_ID did not appear in the dictionary of data up to 10g.

  Try with:

  SELECT DECODE (id, 0, ",)
  LPAD (' ', 2 *(level-1)). level: '. ' || position) | » '|| operation |
  DECODE (id, 0, ",' Option: '). options of |
  DECODE (id, 0, ", the name of the object: '). DECODE (id, 0, ", NVL (object_name, 'None')) |
  DECODE (id, 0, ",' item number: '). Decode (ID, 0, ", NVL (to_char(Object#), 'None')) |
  DECODE (id, 0,' cost = ' | position)
  SQL_Query_plan
  V $ sql_plan
  CONNECT BY prior id = parent_id
  AND address = upper('&&SQLADDRESS')
  START WITH id = 0 AND address = upper('&&SQLADDRESS');

  Currently, I have not all 9i db, so I can't tell you exactly, but I think you're going to tell me something like above, i.e. of the same my previous link. In the above query simply paste the address sql you want to know az7r9swp (without the quotes) as you do.

  Concerning
  Girish Sharma

• TO_DATE and to_char

  Hello
  
  Can someone explain to me why
  
  Select to_date (to_char (to_date('17.05.0012','dd.mm.yyyy'), 'dd'), 'dd.mm.rr') of double
  gives * 17.05.0012 * (what I think wrongly), but
  
  Select to_date (to_char (to_date('17.05.0012','dd.mm.yyyy'), ' dd.mm.yy' ")" | ") "dd.mm.rr") of the double
  gives * 17.05.2012 *.
  
  Thank you!

  Ok thank you! Seems it is explained more or less (only I can't do a patch, it is not my private Oracle).
  I asked a different colleague with Oracle to test and she got good results for 10.1 and 10.2.
  Well, it's not the biggest bug of my life! I'll close the question and thanks for the help!

• Using to_char in order to extract "WW".

  Hello
  The other day asked me to write a sql statement that retrieves the number of weeks per year...

  with sample as 
  
    (select yr
  
      from
  
       (select 1999+level yr
  
         from dual 
  
         connect by rownum<level+1
  
        )
  
    )    
  
    select yr, to_char(to_date('30/12'||yr,'dd/mm/rrrr'),'WW') dt
  
      from sample

  The above query returns the data correctly... but when I try:
  (the difference is written in "BOLD", I get the same number of weeks for each year - which is obviously not correct)

  with sample as 
  
    (select YR
  
      from
  
       (select 1999+level YR
  
         from DUAL 
  
         connect by rownum<level+1
  
        )
  
    )    
  
    select YR, TO_CHAR(TO_DATE('*31*/12'||YR,'dd/mm/rrrr'),'WW') DT
  
      from sample

  Can someone describe why is this difference...?
  
  Note: I use db 10g v.2
  Thank you
  SIM

  Hi, Sim,

  sgalaxy wrote:
  Hello
  The other day asked me to write a sql statement that retrieves the number of weeks per year...

  A the applicant explains exactly what that means.

  with sample as (select yrfrom(select 1999+level yrfrom dual connect by rownum
  The above query returns the data correctly...

  Is this really good? It seems to say that all ordinary years (i.e., the years with only 28 days in February) have 52 weeks, and all this leap years (years where there is a 29 February) have 53 weeks.

  but when I try:
  (the difference is written in "BOLD", I get the same number of weeks for each year - which is obviously not correct)

  Why not? Every year (at least in the Gregorian calendar) have the same number of months. Why every year cannot have the same number of weeks?

  with sample as (select YRfrom(select 1999+level YRfrom DUAL connect by rownum
  Can someone describe why is this difference...?

  To study in detail what Peter said:
  WW '01' is always January 1 to January 7.
  WW '02' is always on January 8 to January 14.
  WW '03' is always on 15 January until 21 January.
  ...
  WW '08' is always from February 19 to February 25.
  WW '09' is February 26 March 4 in common years, but in leap years, it is February 26 to March 3.
  WW '10' is March 5 March 11 in common years, but in leap years, it is from March 4 to March 10.
  ...
  WW '52' is December 24, but on 30 December in common years, but in leap years, it is December 23 to December 29.
  WW '53' is December 31, (only 1 day) in common, but in leap years, it is December 30 and December 31.
  It is therefore 31 December always in week '53'. December 30 is in week 52 ' in common years, but in leap years, it is in week 53'. Looking at the week which includes December 30, you get '52' to 3 over 4 years and 53' like clockwork every 4th year (except at the turn of the century most).

  According to the definition of "WW" for a week, calendar years always have all 52 weeks (seen 7 days each), plus 1 week defective (having only 1 or 2 days).
  A different definition of a 'week' (and year) is the definition of ISO, where all weeks begin on Monday, and all the weeks have 7 days. The ISO year starts the Monday closest to January 1. Using these definitions, most years consist of 52 weeks, but every 5 or 6 years a year ago with 53 weeks.
  The display of the query after the last day of several weeks of ISO and watch what week they are in (which is the total number of weeks this year from ISO).

  SELECT     TO_CHAR ( TRUNC ( ADD_MONTHS ( DATE '2000-07-01'
                                    , 12 * LEVEL
                           )
                   , 'IYYY'
                 ) - 1
            , 'DD-Mon-YYYY   IYYY IW'
            )    AS iso_info
  FROM     dual
  CONNECT BY     LEVEL     <= 25
  ;
  

  When I try to understand nested expressions, like the preceding, I find this helps them to read from the inside (i.e., the more deeply nested point) and then work outward.
  ADD_MONTHS (DATE "2000-07-01', 12 * LEVEL") is 1 July of some year, which is in the middle of the ISO year.
  TRUNC (ADD_MONTHS (DATE "2000-07-01', 12 * LEVEL"), "IYYY") is the first day of a year of ISO.
  TRUNC (ADD_MONTHS (DATE "2000-07-01', 12 * LEVEL"), 'IYYY')-1 is the last day of a year of ISO.
  The result of the above query is:

  ISO_INFO
  ------------------------
  31-Dec-2000   2000 52
  30-Dec-2001   2001 52
  29-Dec-2002   2002 52
  28-Dec-2003   2003 52
  02-Jan-2005   2004 53
  01-Jan-2006   2005 52
  31-Dec-2006   2006 52
  30-Dec-2007   2007 52
  28-Dec-2008   2008 52
  03-Jan-2010   2009 53
  02-Jan-2011   2010 52
  01-Jan-2012   2011 52
  30-Dec-2012   2012 52
  29-Dec-2013   2013 52
  28-Dec-2014   2014 52
  03-Jan-2016   2015 53
  01-Jan-2017   2016 52
  31-Dec-2017   2017 52
  30-Dec-2018   2018 52
  29-Dec-2019   2019 52
  03-Jan-2021   2020 53
  02-Jan-2022   2021 52
  01-Jan-2023   2022 52
  31-Dec-2023   2023 52
  29-Dec-2024   2024 52
  

  There are many other ways to define the 'week' and 'year '.
  For example, we could say that all weeks begin on Sunday and I have 7 days a year start the Sunday closest to January 1.
  Another example: one could say that all weeks begin on Sunday and I have 7 days and a year beginning the first Sunday after December 31.
  In any case, there's how many weeks in a year depends on what your definition of 'week' and 'year '. If you hear the word 'year' out of context, there is a good chance that the speaker refers to the period that begins on 1 January and ends on 31 December. If you hear "week" out of context, there is much less certainty what the speaker means.

• Doubt to_char

  Could someone explain to me the meaning of:
  
  To_char(hire_date-1,'d')
  
  The question is:
  
  Create a query that displays the emp surname, hire_date and the day began. The label for the Date column.
  Sort the results by the day of the week from Monday.
  
  Soln:
  
  Select last_name, hire_date, TO_CHAR (hire_date, 'DAY') DAY
  employees
  order by TO_CHAR (hire_date-1, 'd');
  
  How does the order of?

  Hello

  Try to view the expression did you place your order BY and see:

  select        last_name
  ,       hire_date
  ,       TO_CHAR (hire_date, 'DAY')      AS DAY
  ,       TO_CHAR (hire_date - 1, 'd')     AS order_by_exp          -- For testing only
  from        employees
  order by  TO_CHAR (hire_date - 1, 'd');
  

  To_char ("dt," d ") returns '1' if dt is a Sunday,"2"If dt is a Monday,...,"7"If dt is a Saturday (depending on your settings for NLS_TERRITORY).
  If you would be perfect for ORDER BY Sunday come first, but you want the first come Monday (1 day later). So if you subtract 1 day from dt and use
  To_char (dt - 1, '), then you'll have an expression that returns the value '1' if dt is a Monday (and therefore, dt-1 is a Sunday), "2" If dt is a Tuesday (and dt-1 is a Monday),..., "7" If dt is a Sunday (dt-1 Saturday) and (depending on your settings for NLS_TERRITORY).

• Using NVL and to_char

  Hi guys,.
  
  Help needed here; I use the following code to create a report in Oracle APEX 3.0:
  
  Select 'EBA_BT_PROBLEM '. "" ID "as the"BUG ID. "
  'EBA_BT_PROBLEM '. "" Subject of "as"TOPIC ",.
  'EBA_BT_URGENCY '. "" URGENCY_NAME "as a"PRIORITY. "
  'EBA_BT_USER '. "" New_login_name "as" ASSIGNED to "
  'EBA_BT_PROBLEM '. "' SUBMITTED_BY_ID ' as ' PRESENTED BY '.
  
  of "EBA_BT_PROBLEM" INNER JOIN "EBA_BT_USER" ON "EBA_BT_PROBLEM". "" ASSIGNED_TO_ID "="EBA_BT_USER. " "" IDENTITY CARD ".
  "JOIN THE"EBA_BT_URGENCY"ON"EBA_BT_PROBLEM" URGENCY_ID"="EBA_BT_URGENCY. " "" IDENTITY CARD ".
  "JOIN THE"EBA_BT_STATUS"ON"EBA_BT_PROBLEM" BATCH.
  = "EBA_BT_STATUS". "" IDENTITY CARD ".
  "JOIN THE"EBA_BT_PRODUCT"ON"EBA_BT_PROBLEM" PRODUCT_ID.
  = "EBA_BT_PRODUCT". "" IDENTITY CARD ".
  "JOIN THE"EBA_BT_CATEGORY"ON"EBA_BT_PROBLEM" STUFF. "
  = "EBA_BT_CATEGORY". "" IDENTITY CARD ".
  
  where
  TO_CHAR ("EBA_BT_PROBLEM". "Batch") = NVL (: P64_STATUS, to_char ("EBA_BT_PROBLEM".) " BATCH'))
  
  It returns all the fields and the data I'm after, is the only issue I'm having with my 'where '. I have a drop down selection called P64_STATUS, box that lets choose me among several options that will give me in turn to report different results. He does this ok, but when it is set to the value 'null' or a default, I want to just give me all the possible lines to select it; Instead he gives me nothing.
  
  So essentially, I need to correct the code in my where clause, I think especially here:
  NVL (: P64_STATUS, to_char (* 'EBA_BT_PROBLEM'.)) (("" BATCH "*))
  in order to give me what I'm after
  
  I tried to explain what I'm after as best I can, any help would be much appreciated. Thank you!

  In APEX NULL values, or often "null %. Then you might want to check for this in your selection.

  See also: http://www.inside-oracle-apex.com/display-null-yes-and-null-problem/

  where
  (to_char("EBA_BT_PROBLEM"."STATUS_ID") = :P64_STATUS
    or :P64_STATUS is null
    or :P64_STATUS = '%null%')
  

  You can also assign the value null to the selection list something like -1. Then the number conversion should work

  where  EBA_BT_PROBLEM.STATUS_ID = decode(:P64_STATUS,
                                             '-1', EBA_BT_PROBLEM.STATUS_ID,
                                             null, EBA_BT_PROBLEM.STATUS_ID,
                                             to_number(:P64_STATUS) )
  

  Published by: Sven w. on April 27, 2011 17:29

  Published by: Sven w. on April 27, 2011 17:31

• using to_char ('date', IW) in a different way

  Hello all;
  
  I have the sample data below
  

  create table table_one
  (
   v_id varchar2(60),
   close_date date
  );
  
  insert into table_one
    (v_id, close_date)
  values
    ('A', to_date('1/1/2010 4:47:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
  insert into table_one
    (v_id, close_date)
  values
    ('A', to_date('1/2/2010 2:47:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
  insert into table_one
    (v_id, close_date)
  values
    ('A', to_date('1/3/2010 1:47:19 PM', 'MM/DD/YYYY HH:MI:SS:AM'));   
  insert into table_one
    (v_id, close_date)
  values
    ('D', to_date('1/4/2010 5:47:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
  insert into table_one
    (v_id, close_date)
  values
    ('D', to_date('1/5/2010 4:47:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
  insert into table_one
    (v_id, close_date)
  values
    ('D', to_date('1/6/2010 5:17:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
  
  
  insert into table_one
    (v_id, close_date)
  values
    ('D', to_date('1/7/2010 5:17:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
    insert into table_one
    (v_id, close_date)
  values
    ('D', to_date('1/8/2010 5:17:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
    insert into table_one
    (v_id, close_date)
  values
    ('D', to_date('1/9/2010 5:17:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
    insert into table_one
    (v_id, close_date)
  values
    ('D', to_date('1/10/2010 5:17:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
    insert into table_one
    (v_id, close_date)
  values
    ('L', to_date('1/11/2010 5:17:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
    insert into table_one
    (v_id, close_date)
  values
    ('L', to_date('1/12/2010 5:17:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
    insert into table_one
    (v_id, close_date)
  values
    ('L', to_date('1/13/2010 5:17:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  
      insert into table_one
    (v_id, close_date)
  values
    ('L', to_date('1/14/2010 5:17:09 PM', 'MM/DD/YYYY HH:MI:SS:AM'));  

  and basically, I have the following sql to be changed
  

    select y.v_id, to_char(y.close_date, 'IW') as d_date   from table_one y
    group by to_char(y.close_date, 'IW'), y.v_id;

  this query gives me this output below
  
  V_ID     D_DATE
  D              01
  L               02
  A               53

  However, although that's what I want instead
  

  V_ID             D_DATE
  D                 1/4/2010  - 1/10/2010
  L                  1/11/2010 - 1/17/2010
  A                 1/1/2010 - 1/3/2010

  This is based on the ISO week. Thank you.
  Any help is appreciated

  Hello

  Thanks for posting the CREATE TABLE and INSERT statements; It is very useful.
  It would be even more useful if you explain how you get the results you want from this sample data.
  Rather than display the week number of the group, it seems that you want to display the first and last date of the group. Is this fair?

  If so:

  SELECT    y.v_id
  ,       TO_CHAR ( MIN (y.close_date)
                , 'fmMM/DD/YYYY'
              )
        ||  ' - '
        ||  TO_CHAR ( MAX (y.close_date)
                , 'fmMM/DD/YYYY'
              )     AS d_date
  FROM       table_one     y
  GROUP BY  TO_CHAR (y.close_date, 'IW')
  ,            y.v_id;
  

• How to create indexes based for TO_CHAR function

  I need to create an index of feature based for the to_char.when function I tried, I got an error, "only pure function can be indexed".which the error really means, help me in the creation of the index in order to reduce my query cost.

  It works fine on my database. version 9iR2

  create index IDX_TO_CHAR on emp(to_char(hiredate,'YYYY-MM-DD HH24:MI:SS'));
  
  explain plan for
  select hiredate from emp where to_char(hiredate,'YYYY-MM-DD HH24:MI:SS')='1981-05-01 00:00:00';
  
  ---------------------------------------------------------------------------------
  | Id  | Operation                   |  Name        | Rows  | Bytes | Cost (%CPU)|
  ---------------------------------------------------------------------------------
  |   0 | SELECT STATEMENT            |              |     1 |     8 |     2  (50)|
  |   1 |  TABLE ACCESS BY INDEX ROWID| EMP          |     1 |     8 |     2  (50)|
  |*  2 |   INDEX RANGE SCAN          | IDX_TO_CHAR  |     1 |       |     2  (50)|
  ---------------------------------------------------------------------------------
  
  Predicate Information (identified by operation id):
  ---------------------------------------------------
  
     2 - access(TO_CHAR("EMP"."HIREDATE",'YYYY-MM-DD HH24:MI:SS')='1981-05-01 00
                :00:00')
  

  Your not seem to be a setting issue, then why not give us your sql and execution plan and so on.
  There may be other ways to solve your sql as the creation of a function based index?

• Explain

  Hello
  
  Can someone this query?
  
  
  Select last_name, hire_date, to_char(hire_date,'Day') day, to_char(hire_date-1,'d')
  employees
  order of to_char (hire_date-1, 'day');
  
  
  AR,

  OK, maybe I explaining well...

  You are displaying hiredate, but you order by hiredate - 1

  As explained above, when you use the format mask 'day', he will order as 'Friday', 'Monday', 'Saturday', 'Sunday', 'Thursday', 'Tuesday', 'Wednesday' (for date of hire - 1) so when you view hiredate you will see in the order 'Saturday', 'Tuesday', 'Sunday', 'Monday', 'Friday', 'Wednesday', 'Thursday '.

  The date format mask would be "on the other hand returns a number 1-7 for the day of the week, 1 being Sunday, so he removes 1 date of hiring and to convert a number from 1 to 7, so values when hiredate-1 is a Sunday will sort all first know where hiredate is a Monday and then will sort in the day of the order of the week from there."

  Hope this clears up things.

• To_char (number) gives error ORA-01481

  Hi all
  can someone help me with this delicate error?
  
  Select double to_char(1234.56,'$99,999.99'); -> works
  Select double to_char(1234.56,'$99G999D99'); -> works
  Select double to_char(1234.56,'$99,999D99'); -> Error ORA-01481
  Select double to_char(1234.56,'$99D999.99'); -> Error ORA-01481
  
  Why?
  
  In the reference SQL 11 g there are no written that. and should not be mixed with D and G...
  
  Can someone explain to me why this happens?
  
  Thank you

  Mix of period and comma with D and G can lead to an inconsistent format model.
  Actually G and D can be translated into comma or period comma depending on your NLS settings (and this may change at every moment and every session by session).
  If Oracle cannot check if your template format is correct or not and triggers the error.

  Max