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user8094217 wrote:If you don't know what columns are being returned from a query then you are working from a poorly designed specification and should send it back to your technical design team to request that the requirements are clearly specified. All requirements should have known inputs and known outputs, otherwise it's just wasting people's time.
Thanks for ur quick reply..
but tell me, just in case i do not know the columns which the cursor fetches from the procedure, that means I dont have any clue regarding the output recordset what columns it contains. In that case if I want to print it as a whole, is it possible??
It is possible to write queries that return an unknown number of columns and then query that data from those columns, but this is done positionally (i.e. referencing the columns by number) rather than by name. In 10g, for example, you would have to use the DBMS_SQL package to write a DBMS_SQL cursor and then process that cursor for it's columns and data... e.g.
As sys user:
CREATE OR REPLACE DIRECTORY TEST_DIR AS '\tmp\myfiles' / GRANT READ, WRITE ON DIRECTORY TEST_DIR TO myuser /
This allows for the header row and the data to be written to seperate files if required.
CREATE OR REPLACE PROCEDURE run_query(p_sql IN VARCHAR2 ,p_dir IN VARCHAR2 ,p_header_file IN VARCHAR2 ,p_data_file IN VARCHAR2 := NULL) IS v_finaltxt VARCHAR2(4000); v_v_val VARCHAR2(4000); v_n_val NUMBER; v_d_val DATE; v_ret NUMBER; c NUMBER; d NUMBER; col_cnt INTEGER; f BOOLEAN; rec_tab DBMS_SQL.DESC_TAB; col_num NUMBER; v_fh UTL_FILE.FILE_TYPE; v_samefile BOOLEAN := (NVL(p_data_file,p_header_file) = p_header_file); BEGIN c := DBMS_SQL.OPEN_CURSOR; DBMS_SQL.PARSE(c, p_sql, DBMS_SQL.NATIVE); d := DBMS_SQL.EXECUTE(c); DBMS_SQL.DESCRIBE_COLUMNS(c, col_cnt, rec_tab); FOR j in 1..col_cnt LOOP CASE rec_tab(j).col_type WHEN 1 THEN DBMS_SQL.DEFINE_COLUMN(c,j,v_v_val,2000); WHEN 2 THEN DBMS_SQL.DEFINE_COLUMN(c,j,v_n_val); WHEN 12 THEN DBMS_SQL.DEFINE_COLUMN(c,j,v_d_val); ELSE DBMS_SQL.DEFINE_COLUMN(c,j,v_v_val,2000); END CASE; END LOOP; -- This part outputs the HEADER v_fh := UTL_FILE.FOPEN(upper(p_dir),p_header_file,'w',32767); FOR j in 1..col_cnt LOOP v_finaltxt := ltrim(v_finaltxt||','||lower(rec_tab(j).col_name),','); END LOOP; -- DBMS_OUTPUT.PUT_LINE(v_finaltxt); UTL_FILE.PUT_LINE(v_fh, v_finaltxt); IF NOT v_samefile THEN UTL_FILE.FCLOSE(v_fh); END IF; -- -- This part outputs the DATA IF NOT v_samefile THEN v_fh := UTL_FILE.FOPEN(upper(p_dir),p_data_file,'w',32767); END IF; LOOP v_ret := DBMS_SQL.FETCH_ROWS(c); EXIT WHEN v_ret = 0; v_finaltxt := NULL; FOR j in 1..col_cnt LOOP CASE rec_tab(j).col_type WHEN 1 THEN DBMS_SQL.COLUMN_VALUE(c,j,v_v_val); v_finaltxt := ltrim(v_finaltxt||',"'||v_v_val||'"',','); WHEN 2 THEN DBMS_SQL.COLUMN_VALUE(c,j,v_n_val); v_finaltxt := ltrim(v_finaltxt||','||v_n_val,','); WHEN 12 THEN DBMS_SQL.COLUMN_VALUE(c,j,v_d_val); v_finaltxt := ltrim(v_finaltxt||','||to_char(v_d_val,'DD/MM/YYYY HH24:MI:SS'),','); ELSE v_finaltxt := ltrim(v_finaltxt||',"'||v_v_val||'"',','); END CASE; END LOOP; -- DBMS_OUTPUT.PUT_LINE(v_finaltxt); UTL_FILE.PUT_LINE(v_fh, v_finaltxt); END LOOP; UTL_FILE.FCLOSE(v_fh); DBMS_SQL.CLOSE_CURSOR(c); END;
Output.txt file contains:
SQL> exec run_query('select * from emp','TEST_DIR','output.txt'); PL/SQL procedure successfully completed.
If you are using 11g, you can take a ref cursor and then use a new function called TO_CURSOR_NUMBER in the DBMS_SQL package (http://download.oracle.com/docs/cd/B28359_01/appdev.111/b28370/dynamic.htm#BHCBJGEH) which can convert the ref cursor to a dbms_sql cursor for which you can then do the same thing as above to query and extract the data.
empno,ename,job,mgr,hiredate,sal,comm,deptno 7369,"SMITH","CLERK",7902,17/12/1980 00:00:00,800,,20 7499,"ALLEN","SALESMAN",7698,20/02/1981 00:00:00,1600,300,30 7521,"WARD","SALESMAN",7698,22/02/1981 00:00:00,1250,500,30 7566,"JONES","MANAGER",7839,02/04/1981 00:00:00,2975,,20 7654,"MARTIN","SALESMAN",7698,28/09/1981 00:00:00,1250,1400,30 7698,"BLAKE","MANAGER",7839,01/05/1981 00:00:00,2850,,30 7782,"CLARK","MANAGER",7839,09/06/1981 00:00:00,2450,,10 7788,"SCOTT","ANALYST",7566,19/04/1987 00:00:00,3000,,20 7839,"KING","PRESIDENT",,17/11/1981 00:00:00,5000,,10 7844,"TURNER","SALESMAN",7698,08/09/1981 00:00:00,1500,0,30 7876,"ADAMS","CLERK",7788,23/05/1987 00:00:00,1100,,20 7900,"JAMES","CLERK",7698,03/12/1981 00:00:00,950,,30 7902,"FORD","ANALYST",7566,03/12/1981 00:00:00,3000,,20 7934,"MILLER","CLERK",7782,23/01/1982 00:00:00,1300,,10