exporting data to a flat file

[trogen]

How do I export a certain column in a table onto a flat ascii file?

[sreddy]

Oracle doesn't supply any data unload tools. However, you can use the following like query to unload and format. here is some oracle provided script for this in metalink, I will post it when I find.

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set echo off newpage 0 space 0 pagesize 0 feed off head off trimspool on
spool oradata.txt
select col1 || ',' || col2 || ',' || col3
from tab1
where col2 = 'XYZ';
spool off

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SQL> SPOOL text_file.txt
SQL> select column_name from table_name;
SQL> SPOOL off

or

You write a PL/SQL block and use UTL_FILE packaged procedures and select the information from the table using cursor and write it to flat file.

Hope this information helps.

-AD

[trogen]

Thats a great help.
But is there a way I can execute all this from the linux command prompt?
Because currently I would have to log in to sqlplus and then execute. Could I do this somehow from the command prompt?

[sreddy]

Operating system can't directly talk to database with no database utilities. You are talking about getting data from database table. How will you get from table with no connection to database. Nothing strike my mind...if someone has idea great add on for the tips I am aware of....

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From UNIX OS you can use sqlplus -s uid/pwd @file.sql command to logon to your database and execute the sql. But not aware of Linux commands. Check out the Linus manuals for the appropriate commands on how to logon to Database.

Thanks,
AD

[marist89]

See
[url]http://govt.oracle.com/~tkyte/flat/index.html[/url]

[sreddy]

I din't test the script, but one of my co-dba tested it and says it works.

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SET ECHO off
REM --------------------------------------------------------------------------
REM REQUIREMENTS:
REM SELECT on the given table(s)
REM --------------------------------------------------------------------------
REM PURPOSE:
REM Generates a sql*plus script to unload a table to a file and a
REM SQL*Loader script to reload the same data. Intent is to create
REM a faster alternative to export/import.
REM ---------------------------------------------------------------------------
REM DISCLAIMER:
REM This script is provided for educational purposes only. It is NOT
REM supported by Oracle World Wide Technical Support.
REM The script has been tested and appears to work as intended.
REM You should always run new scripts on a test instance initially.
REM --------------------------------------------------------------------------
REM Main text of script follows:

set tab off
set heading off heading off feedback off echo off verify off space 1 pagesize 0 linesize 120
accept owner prompt 'What schema owns the table to be unloaded? '
accept table_name prompt 'What table is to be unloaded? '
accept default_precision prompt 'Total number of digits to be reserved for numbrs w/out defined precision?'
accept default_scale prompt 'Total number of DECIMAL digits to be reserved for numbers w/out defined scale? '
---------------------------------------------------
-- Generate the unload script
---------------------------------------------------
spool unload_fixed2.sql
select 'SET HEADING OFF FEEDBACK OFF ECHO OFF VERIFY OFF SPACE 0 PAGESIZE 0
TERMOUT OFF'
from dual
/

--Calculate the sum of all output field lengths and set the output record size
select 'SET LINESIZE '
|| (sum(decode(data_type,
'CHAR',data_length,
'VARCHAR',data_length,
'VARCHAR2',data_length,
'DATE',14,
'NUMBER',decode(data_precision,
'',&default_precision+2,
greatest(data_precision-data_scale,1)+decode(data_scale,0,0,1)+data_scale)+1,
'FLOAT',&default_precision+2,
data_length)))
from dba_tab_columns
where owner=upper('&&owner')
and table_name=upper('&&table_name')
/

-- Generate an appropriate SQL*Plus COLUMN command to control formatting of
-- each output field
select 'COLUMN ' || rpad('"'||column_name||'"',32)
|| ' FORMAT '
|| rpad(decode(data_type,
'CHAR','A'||data_length,
'VARCHAR2','A'||data_length,
'VARCHAR','A'||data_length,'DATE','A14',
'NUMBER',decode(data_precision,'',rpad('0',&default_precision-&default_scale,'9')||'.'
||rpad('9',&default_scale,'9'), rpad('0',greatest(data_precision-data_scale,1),'9') ||
decode(data_scale,0,'','.') ||
decode(data_scale,0,'',rpad('9',data_scale,'9'))),
'FLOAT',rpad('0',&default_precision-&default_scale,'9')||'.'||rpad('9',&default_scale,'9'),
'ERROR'),40)|| ' HEADING ''X'''
from dba_tab_columns
where owner=upper('&&owner')
and table_name=upper('&&table_name')
order by column_id
/
-- Generate the actual SELECT statement to unload table data
select 'SPOOL /tmp/&&owner..&&table_name..DAT'
from dual
/
column var1 noprint
column var2 noprint
select 'a' var1, 0 var2, 'SELECT '
from dual
union
select 'b', column_id, decode(column_id, 1, ' ', ' , ')||
decode(data_type,'DATE','to_char('||'"'||column_name||'"'||',''YYYYMMDDHH24MISS
'') '||'"'||column_name||'"' ,
'"'||column_name||'"')
from dba_tab_columns
where owner=upper('&&owner')
and table_name=upper('&&table_name')
union
select 'c', 0, 'FROM &&owner..&&table_name'
from dual
union
select 'd', 0, ';'
from dual
order by 1,2
/
select 'SPOOL OFF'
from dual
/
select 'SET TERMOUT ON'
from dual
/

spool off
-----------------------------------------------------------------------------
-- Generate the SQL*Loader control file
-----------------------------------------------------------------------------
set lines 120 pages 0
spool &&owner..&&table_name..CTL
select 'a' var1, 0 var2, 'OPTIONS(DIRECT=TRUE)'
from dual
union
select 'b', 0, 'LOAD DATA'
from dual
union
select 'c', 0, 'INFILE ''/tmp/&&owner..&&table_name..DAT'''
from dual
union
select 'd', 0, 'BADFILE &&owner..&&table_name..BAD'
from dual
union
select 'e', 0, 'DISCARDFILE &&owner..&&table_name..DSC'
from dual
union
select 'f', 0, 'DISCARDMAX 999'
from dual
union
select 'm', 0, 'INTO TABLE &&owner..&&table_name'
from dual
union
select 'n', column_id,
rpad(decode(column_id,1,'(',',')||'"'||column_name||'"',31)
|| decode(data_type,
'CHAR','CHAR('||data_length||')',
'VARCHAR','CHAR('||data_length||')',
'VARCHAR2','CHAR('||data_length||')',
'DATE','DATE(14) "YYYYMMDDHH24MISS"',
'NUMBER','DECIMAL
EXTERNAL('||decode(data_precision,
'',&default_precision+2, greatest(data_precision-data_scale,1)+decode(data_scale,0,0,1)+data_scale+1)
||')',
'FLOAT','DECIMAL
EXTERNAL('||to_char(&default_precision+2)||')',
'ERROR--'||data_type)
|| ' NULLIF ("' ||column_name||'" = BLANKS)'
from dba_tab_columns
where owner = upper('&&owner')
and table_name = upper('&&table_name')
union
select 'z', 0, ')'
from dual
order by 1, 2
/

spool off

-----------------------------------------------------------------------------
-- Cleanup
-----------------------------------------------------------------------------
clear column
clear break
clear compute
undef owner
undef table_name
undef default_precision
undef default_scale

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