How can I use SQL to search for a pattern within a field?

Question

Hello, Frank, Solomon, ect
I am now faced with this particular scenario, I've got the SQL to search through a field to find text within the field, but I have to know what it is before it can look for it.
What I have to do is this:
Search through a field, for a pattern, and I won't know what the data is I am looking for. Can this be done in SQL?
For instance, Here is my SQL this far, I was helped allot in order to get to this point.
select table_name,
       column_name,
       :search_string search_string,
       result
  from (select column_name,
               table_name,
               'ora:view("' || table_name || '")/ROW/' || column_name || '[ora:contains(text(),"%' || :search_string || '%") > 0]' str
          from cols
         where table_name in ('TABLE1', 'TABLE2')),
       xmltable (str columns result varchar2(10) path '.')
When you execute the above SQL, you have to pass in a value. What I really need is to alter the above SQL, to make it search for a pattern that exist's within the text of the field itself.
Like for instance, lets say the pattern I am looking for is this" xx-xxxxx-xxxx" and it's somewhere in a field.
I need to alter this SQL to take this pattern and search through all the schemas and tables to look for this pattern match.
Can be done?

Answer 1

When you use something dynamically within a function or procedure, roles do not apply and privileges must be granted directly.  So, you need to grant select on dba_tab_cols directly.  If you want to do pattern matching then you should use regular expressions.  The following example grants the proper privileges and uses regexp_instr to find all values containing the pattern xxx-xxxx-xxxx, where /S is used for any non-space character.  I limited the tables in order to save time and output for the test, but you can eliminate that where clause.
SYS@orcl> CREATE USER test IDENTIFIED BY test
  2  /
User created.
SYS@orcl> ALTER USER test QUOTA UNLIMITED ON USERS
  2  /
User altered.
SYS@orcl> GRANT CREATE SESSION, CREATE TABLE TO test
  2  /
Grant succeeded.
SYS@orcl> GRANT SELECT ON dba_tab_cols TO test
  2  /
Grant succeeded.
SYS@orcl> CONNECT test/test
Connected.
TEST@orcl> SET LINESIZE 90
TEST@orcl> CREATE TABLE table1
  2    (tab1_col1  VARCHAR2(60))
  3  /
Table created.
TEST@orcl> INSERT ALL
  2  INTO table1 (tab1_col1) VALUES ('xxx-xxxx-xxxx')
  3  INTO table1 (tab1_col1) VALUES ('matching abc-defg-hijk data')
  4  INTO table1 (tab1_col1) VALUES ('other data')
  5  SELECT * FROM DUAL
  6  /
3 rows created.
TEST@orcl> CREATE TABLE table2
  2    (tab2_col2  VARCHAR2(30))
  3  /
Table created.
TEST@orcl> INSERT ALL
  2  INTO table2 (tab2_col2) VALUES ('this BCD-EFGH-IJKL too')
  3  INTO table2 (tab2_col2) VALUES ('something else')
  4  SELECT * FROM DUAL
  5  /
2 rows created.
TEST@orcl> VAR search_string VARCHAR2(24)
TEST@orcl> EXEC :search_string := '\S\S\S-\S\S\S\S-\S\S\S\S'
PL/SQL procedure successfully completed.
TEST@orcl> COLUMN "Searchword"     FORMAT A24
TEST@orcl> COLUMN "Table"     FORMAT A6
TEST@orcl> COLUMN "Column/Value" FORMAT A50
TEST@orcl> SELECT DISTINCT SUBSTR (:search_string, 1, 24) "Searchword",
  2               SUBSTR (table_name, 1, 14) "Table",
  3               SUBSTR (t.column_value.getstringval (), 1, 50) "Column/Value"
  4  FROM   dba_tab_cols,
  5          TABLE
  6            (XMLSEQUENCE
  7           (DBMS_XMLGEN.GETXMLTYPE
  8              ( 'SELECT ' || column_name ||
  9               ' FROM ' || table_name ||
10               ' WHERE REGEXP_INSTR
11                     (UPPER (' || column_name || '),''' ||
12                  UPPER (:search_string) || ''') > 0'
13              ).extract ('ROWSET/ROW/*'))) t
14  WHERE  table_name IN ('TABLE1', 'TABLE2')
15  ORDER  BY "Table"
16  /
Searchword               Table  Column/Value
\S\S\S-\S\S\S\S-\S\S\S\S TABLE1 <TAB1_COL1>matching abc-defg-hijk data</TAB1_COL1>
\S\S\S-\S\S\S\S-\S\S\S\S TABLE1 <TAB1_COL1>xxx-xxxx-xxxx</TAB1_COL1>
\S\S\S-\S\S\S\S-\S\S\S\S TABLE2 <TAB2_COL2>this BCD-EFGH-IJKL too</TAB2_COL2>
3 rows selected.