Oracle PL/SQL Tutorial/Regular Expressions Functions/Brackets

A match for any vowel followed by an "r" or "p"

SQL>
SQL> -- create demo table
SQL> create table myTable(
  2    id           NUMBER(2),
  3    value        VARCHAR(50)
  4  );
Table created.
SQL>
SQL> insert into myTable(id, value)values(1,"1234 4th St. Vancouver");
1 row created.
SQL> insert into myTable(id, value)values(2,"4 Maple Ct. New York");
1 row created.
SQL> insert into myTable(id, value)values(3,"4321 Green Blvd. London");
1 row created.
SQL> insert into myTable(id, value)values(4,"33 Third St. Toronto");
1 row created.
SQL> insert into myTable(id, value)values(5,"One First Drive. Queen");
1 row created.
SQL> insert into myTable(id, value)values(6,"1664 1/2 Springhill Ave");
1 row created.
SQL> insert into myTable(id, value)values(7,"665 Fall Ave. Linken");
1 row created.
SQL>
SQL> select * from mytable;
        ID VALUE
---------- --------------------------------------------------
         1 1234 4th St. Vancouver
         2 4 Maple Ct. New York
         3 4321 Green Blvd. London
         4 33 Third St. Toronto
         5 One First Drive. Queen
         6 1664 1/2 Springhill Ave
         7 665 Fall Ave. Linken
7 rows selected.
SQL>
SQL> SELECT value, REGEXP_INSTR(value,"[aeiou][rp]") where_it_is
  2  FROM myTable
  3  WHERE REGEXP_INSTR(value,"[aeiou][rp]") > 0;
VALUE                                              WHERE_IT_IS
-------------------------------------------------- -----------
1234 4th St. Vancouver                                      21
4 Maple Ct. New York                                         4
33 Third St. Toronto                                         6
One First Drive. Queen                                       6
SQL>
SQL>
SQL>
SQL> drop table myTable;
Table dropped.
SQL>
SQL>

Brackets

If we use brackets, [whatever], we are asking for a match of whatever set of characters is included inside the brackets in any order.

Suppose we wanted to devise a query to find addresses where there is either an "i" or an "r."

SQL>
SQL> -- create demo table
SQL> create table myTable(
  2    id           NUMBER(2),
  3    value        VARCHAR(50)
  4  );
Table created.
SQL>
SQL> insert into myTable(id, value)values(1,"1234 4th St. Vancouver");
1 row created.
SQL> insert into myTable(id, value)values(2,"4 Maple Ct. New York");
1 row created.
SQL> insert into myTable(id, value)values(3,"4321 Green Blvd. London");
1 row created.
SQL> insert into myTable(id, value)values(4,"33 Third St. Toronto");
1 row created.
SQL> insert into myTable(id, value)values(5,"One First Drive. Queen");
1 row created.
SQL> insert into myTable(id, value)values(6,"1664 1/2 Springhill Ave");
1 row created.
SQL> insert into myTable(id, value)values(7,"665 Fall Ave. Linken");
1 row created.
SQL>
SQL> select * from mytable;
        ID VALUE
---------- --------------------------------------------------
         1 1234 4th St. Vancouver
         2 4 Maple Ct. New York
         3 4321 Green Blvd. London
         4 33 Third St. Toronto
         5 One First Drive. Queen
         6 1664 1/2 Springhill Ave
         7 665 Fall Ave. Linken
7 rows selected.
SQL>
SQL>
SQL> SELECT value, REGEXP_INSTR(value, "[ir]") where_it_is
  2  FROM myTable;
VALUE                                              WHERE_IT_IS
-------------------------------------------------- -----------
1234 4th St. Vancouver                                      22
4 Maple Ct. New York                                        19
4321 Green Blvd. London                                      7
33 Third St. Toronto                                         6
One First Drive. Queen                                       6
1664 1/2 Springhill Ave                                     12
665 Fall Ave. Linken                                        16
7 rows selected.
SQL>
SQL>
SQL> drop table myTable;
Table dropped.
SQL>
SQL>