Example of using XSLT transformation

select xmltransform(xmltype('

  100
  1
  
    
  
'),xmltype(q'{




  
  
    
  





}'))
from dual
  

Out SYS_REFCURSOR into console

create or replace PROCEDURE grachevcur(
                            p_refcursor        IN OUT SYS_REFCURSOR
                         )  
    AS
        l_desc          DBMS_SQL.DESC_TAB ;
        l_cols          BINARY_INTEGER ;
        l_cursor        BINARY_INTEGER ;
        v_varchar2      VARCHAR2( 4000 ) ;
        v_number        NUMBER ;
        v_date          DATE ;
        l_data          varchar2( 32767 ) ;
        l_columnValue   VARCHAR2( 32767 ) ;
        l_processedRows Number := 0;
    BEGIN
 
        /* Convert refcursor "parameter" to DBMS_SQL cursor... */
        l_cursor := DBMS_SQL.TO_CURSOR_NUMBER( p_refcursor );
        /* Describe the cursor... */
        DBMS_SQL.DESCRIBE_COLUMNS( l_cursor, l_cols, l_desc );
 
        /* Define columns to be fetched. We're only using V2, NUM, DATE for example...
        for a complete list of the col_types this link is accessible.
        http://download.oracle.com/docs/cd/B10501_01/server.920/a96540/sql_elements2a.htm#45504
        http://forums.oracle.com/forums/thread.jspa?threadID=912475
        if not a usable type, will throw new exception
        */
         FOR i IN 1 .. l_cols LOOP
             IF l_desc(i).col_type = 2 THEN
               DBMS_SQL.DEFINE_COLUMN(l_cursor, i, v_number);
            ELSIF l_desc(i).col_type = 12 THEN
               DBMS_SQL.DEFINE_COLUMN(l_cursor, i, v_date);
            ELSif l_desc(i).col_type = 01 or l_desc(i).col_type = 96 then
               DBMS_SQL.DEFINE_COLUMN(l_cursor, i, v_varchar2, 4000);
            else
                --raise an exception if the user's query contains a datatype not (yet) supported by this procedure
                RAISE_APPLICATION_ERROR(-20000, 'Invalid Data Type for conversion to delimited file. {' || l_desc(i).col_name || '}');
            END IF;
          END LOOP;
 
 
        /* -- print out the column names if desired
             FOR i IN 1 .. l_cols LOOP
                     dbms_output.put_line('** ' || l_desc(i).col_name) ;
             END LOOP;
        */
 
         /* Fetch all data... */
         WHILE DBMS_SQL.FETCH_ROWS(l_cursor) > 0 LOOP
             dbms_output.put_line('LINE: '  || l_processedRows || '');
             FOR i IN 1 .. l_cols LOOP
                 if l_desc(i).col_type = 12 THEN --we are in a date
                    DBMS_SQL.COLUMN_VALUE(l_cursor, i, v_date);
                    v_varchar2 := to_char(v_date , 'dd-MON-yyyy' ) ;
                 elsif  l_desc(i).col_type = 2 THEN --we are in a number
                    DBMS_SQL.COLUMN_VALUE(l_cursor, i, v_number);
                    v_varchar2 := to_char(v_number) ;
                 else --treat it as a string (should be varchar2,char,etc)
                    DBMS_SQL.COLUMN_VALUE(l_cursor, i, v_varchar2);
                    IF v_varchar2 IS NOT NULL THEN
                       v_varchar2 := '"' || v_varchar2 || '"' ;
                       ELSE
                       v_varchar2 := '';
                    END IF ;
                 end if ;
                 dbms_output.put_line('  ' ||l_desc(i).col_name || '=>' || v_varchar2) ;
             END LOOP;
             l_processedRows := l_processedRows + 1 ;
          END LOOP;
 
          dbms_sql.close_cursor(l_cursor);
          dbms_output.put_line('I found and processed  '  || l_processedRows || ' rows .');
 
    END;
/

How to disable and enable depended constraints

select
--'truncate table '|| TABLE_NAME || ';'
'alter table ' || TABLE_NAME || ' enable constraint ' || CONSTRAINT_NAME || ';'
from ALL_CONSTRAINTS
where CONSTRAINT_TYPE = 'R'
  and STATUS <> 'ENABLED'
  --and R_CONSTRAINT_NAME = 'C_MEDHISTCONS_PK'
order by TABLE_NAME

select 'alter table ' || TABLE_NAME || ' disable constraint ' || CONSTRAINT_NAME || ';'
from ALL_CONSTRAINTS
where CONSTRAINT_TYPE = 'R'
  and R_CONSTRAINT_NAME = 'C_DCSPECS_PK'  

How to create indexes by foreign key

select 'create index I_' || substr(C.CONSTRAINT_NAME, 3) || ' on ' || C.TABLE_NAME || '(' || 
  (select rtrim(xmlagg(xmlelement(e, CC.COLUMN_NAME,',').extract('//text()') order by CC.COLUMN_NAME).GetClobVal(),',')
   from ALL_CONS_COLUMNS CC
   where CC.OWNER = C.OWNER
     and CC.TABLE_NAME = C.TABLE_NAME
     and CC.CONSTRAINT_NAME = C.CONSTRAINT_NAME) || ');'
from (
  select distinct C.OWNER, C.TABLE_NAME, C.CONSTRAINT_NAME
  from
    ALL_CONSTRAINTS C,
    ALL_CONS_COLUMNS CC
  where C.CONSTRAINT_TYPE = 'R'
    and C.OWNER = 'PARUS'
    and CC.OWNER = C.OWNER
    and CC.TABLE_NAME = C.TABLE_NAME
    and CC.CONSTRAINT_NAME = C.CONSTRAINT_NAME
    and not CC.COLUMN_NAME in ('COMPANY', 'VERSION')
    and CC.CONSTRAINT_NAME like 'C\_%' escape '\'
    and not exists (
      select *
      from ALL_IND_COLUMNS IC
      where IC.TABLE_OWNER = C.OWNER
        and IC.TABLE_NAME  = CC.TABLE_NAME
        and IC.COLUMN_NAME = CC.COLUMN_NAME)) C

How to reverse string

select listagg(C) within group(order by RN desc) rvs
from (
  select substr(T.COL, rownum, 1) C, rownum RN
  from (select 'Привет' COL from DUAL) T
  connect by level <= length(T.COL))