Oracle PL/SQL Tutorial/Regular Expressions Functions/REGEXP LIKE — различия между версиями

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Версия 13:45, 26 мая 2010

Asking for the presence of a "g" or a "p"

The "%" sign metacharacter matches zero, one, or more characters.



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
  2  FROM myTable
  3  WHERE value LIKE("%g%")OR value LIKE ("%p%");
VALUE
--------------------------------------------------
4 Maple Ct. New York
1664 1/2 Springhill Ave
SQL>
SQL>
SQL> drop table myTable;
Table dropped.
SQL>
SQL>


Asking for the presence of a "g" or a "p" with REGEXP_LIKE

The order of occurrence of [gp] or [pg] is irrelevant.



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
  2  FROM myTable
  3  WHERE REGEXP_LIKE(value,"[gp]");
VALUE
--------------------------------------------------
4 Maple Ct. New York
1664 1/2 Springhill Ave
SQL>
SQL>
SQL> drop table myTable;
Table dropped.
SQL>
SQL>


Regexp_Like

The complete function definition is:

REGEXP_LIKE(String to search, Pattern, [Parameters]),

where

String to search, Pattern, and Parameters are the same as for REGEXP_INSTR.

As with REGEXP_INSTR, the Parameters argument is usually used only in special situations.

18. 3. REGEXP_LIKE 18. 3. 1. <A href="/Tutorial/Oracle/0360__Regular-Expressions-Functions/REGEXPLIKExpatternmatchoptionsearchsxfortheregularexpressionpattern.htm">REGEXP_LIKE(x, pattern [, match_option]) searchs x for the regular expression pattern.</a> 18. 3. 2. Regexp_Like 18. 3. 3. <A href="/Tutorial/Oracle/0360__Regular-Expressions-Functions/Askingforthepresenceofagorap.htm">Asking for the presence of a "g" or a "p"</a> 18. 3. 4. <A href="/Tutorial/Oracle/0360__Regular-Expressions-Functions/AskingforthepresenceofagorapwithREGEXPLIKE.htm">Asking for the presence of a "g" or a "p" with REGEXP_LIKE</a> 18. 3. 5. <A href="/Tutorial/Oracle/0360__Regular-Expressions-Functions/RetrievesemployeeswhosefirstnamestartswithJorj.htm">Retrieves employees whose first name starts with J or j.</a> 18. 3. 6. <A href="/Tutorial/Oracle/0360__Regular-Expressions-Functions/regexplikecommentsfazi.htm">regexp_like(comments, " f[a-z]* ","i")</a> 18. 3. 7. <A href="/Tutorial/Oracle/0360__Regular-Expressions-Functions/regexplikecomments8.htm">regexp_like(comments, "([^ ]+ ){8,}")</a> 18. 3. 8. <A href="/Tutorial/Oracle/0360__Regular-Expressions-Functions/Usingregexplikecommentsalnumpunctspace8.htm">Using regexp_like(comments, "([[:alnum:]+[:punct:]]+space:+){8,}")</a>

regexp_like(comments, "([^ ]+ ){8,}")

SQL>
SQL> create table history
  2  ( empno      NUMBER(4)
  3  , beginyear  NUMBER(4)
  4  , begindate  DATE
  5  , enddate    DATE
  6  , deptno     NUMBER(2)
  7  , msal       NUMBER(6,2)
  8  , comments   VARCHAR2(60)
  9  ) ;
Table created.
SQL>
SQL>
SQL>
SQL> insert into history values (9,2000,date "2000-01-01",date "2002-01-02",40, 950,"history for 9");
1 row created.
SQL> insert into history values (8,2000,date "2000-01-02", NULL       ,20, 800,"");
1 row created.
SQL> insert into history values (7,1988,date "2000-01-06",date "2002-01-07",30,1000,"");
1 row created.
SQL> insert into history values (6,1989,date "2000-01-07",date "2002-01-12",30,1300,"");
1 row created.
SQL> insert into history values (5,1993,date "2000-01-12",date "2002-01-10",30,1500,"history for 5");
1 row created.
SQL> insert into history values (4,1995,date "2000-01-10",date "2002-01-11",30,1700,"");
1 row created.
SQL> insert into history values (3,1999,date "2000-01-11", NULL       ,30,1600,"");
1 row created.
SQL> insert into history values (2,1986,date "2000-01-10",date "2002-01-08",20,1000,"history for 2");
1 row created.
SQL> insert into history values (1,1987,date "2000-01-08",date "2002-01-01",30,1000,"history for 1");
1 row created.
SQL> insert into history values (7,1989,date "2000-01-01",date "2002-05-12",30,1150,"history for 7");
1 row created.
SQL>
SQL>
SQL>
SQL>
SQL> select comments
  2  from   history
  3  where  regexp_like(comments, "([^ ]+ ){8,}");
no rows selected
SQL>
SQL> drop table history;
Table dropped.


regexp_like(comments, " f[a-z]* ","i")

SQL>
SQL> create table history
  2  ( empno      NUMBER(4)
  3  , beginyear  NUMBER(4)
  4  , begindate  DATE
  5  , enddate    DATE
  6  , deptno     NUMBER(2)
  7  , msal       NUMBER(6,2)
  8  , comments   VARCHAR2(60)
  9  ) ;
Table created.
SQL>
SQL>
SQL>
SQL> insert into history values (9,2000,date "2000-01-01",date "2002-01-02",40, 950,"history for 9");
1 row created.
SQL> insert into history values (8,2000,date "2000-01-02", NULL       ,20, 800,"");
1 row created.
SQL> insert into history values (7,1988,date "2000-01-06",date "2002-01-07",30,1000,"");
1 row created.
SQL> insert into history values (6,1989,date "2000-01-07",date "2002-01-12",30,1300,"");
1 row created.
SQL> insert into history values (5,1993,date "2000-01-12",date "2002-01-10",30,1500,"history for 5");
1 row created.
SQL> insert into history values (4,1995,date "2000-01-10",date "2002-01-11",30,1700,"");
1 row created.
SQL> insert into history values (3,1999,date "2000-01-11", NULL       ,30,1600,"");
1 row created.
SQL> insert into history values (2,1986,date "2000-01-10",date "2002-01-08",20,1000,"history for 2");
1 row created.
SQL> insert into history values (1,1987,date "2000-01-08",date "2002-01-01",30,1000,"history for 1");
1 row created.
SQL> insert into history values (7,1989,date "2000-01-01",date "2002-05-12",30,1150,"history for 7");
1 row created.
SQL>
SQL>
SQL> select regexp_replace(comments, " f[a-z]* "," ? ",1,1,"i")
  2  from   history
  3  where  regexp_like(comments, " f[a-z]* ","i");
REGEXP_REPLACE(COMMENTS,"F[A-Z]*","?",1,1,"I")
----------------------------------------------------------------------------------------------------
history ? 9
history ? 5
history ? 2
history ? 1
history ? 7
SQL>
SQL> drop table history;
Table dropped.
SQL>


REGEXP_LIKE(x, pattern [, match_option]) searchs x for the regular expression pattern.

You can provide an optional match_option string to indicate the default matching.

  1. "c", which specifies case sensitive matching (default).
  2. "i", which specifies case insensitive matching.
  3. "n", which allows you to use the match-any-character operator.
  4. "m", which treats x as multiple line.

The following example retrieves employees whose date of birth is between 1995 and 1998 using REGEXP_LIKE():



SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE)         NOT NULL,
  3    First_Name         VARCHAR2(10 BYTE),
  4    Last_Name          VARCHAR2(10 BYTE),
  5    Start_Date         DATE,
  6    End_Date           DATE,
  7    Salary             Number(8,2),
  8    City               VARCHAR2(10 BYTE),
  9    Description        VARCHAR2(15 BYTE)
 10  )
 11  /
Table created.
SQL>
SQL> -- prepare data
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2               values ("01","Jason",    "Martin",  to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto",  "Programmer")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("02","Alison",   "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("03","James",    "Smith",   to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("04","Celia",    "Rice",    to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("05","Robert",   "Black",   to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("06","Linda",    "Green",   to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York",  "Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("07","David",    "Larry",   to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York",  "Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("08","James",    "Cat",     to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
ID   FIRST_NAME LAST_NAME  START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- ---------- ---------- --------- --------- ---------- ---------- ---------------
01   Jason      Martin     25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL>
SQL>
SQL> SELECT id, first_name, last_name, start_date FROM employee
  2  WHERE REGEXP_LIKE(TO_CHAR(start_date, "YYYY"), "^199[5-8]$");
ID   FIRST_NAME LAST_NAME  START_DAT
---- ---------- ---------- ---------
01   Jason      Martin     25-JUL-96
08   James      Cat        17-SEP-96
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>


Retrieves employees whose first name starts with J or j.

SQL>
SQL>
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE)         NOT NULL,
  3    First_Name         VARCHAR2(10 BYTE),
  4    Last_Name          VARCHAR2(10 BYTE),
  5    Start_Date         DATE,
  6    End_Date           DATE,
  7    Salary             Number(8,2),
  8    City               VARCHAR2(10 BYTE),
  9    Description        VARCHAR2(15 BYTE)
 10  )
 11  /
Table created.
SQL>
SQL> -- prepare data
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2               values ("01","Jason",    "Martin",  to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto",  "Programmer")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("02","Alison",   "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("03","James",    "Smith",   to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("04","Celia",    "Rice",    to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("05","Robert",   "Black",   to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("06","Linda",    "Green",   to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York",  "Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("07","David",    "Larry",   to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York",  "Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("08","James",    "Cat",     to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
ID   FIRST_NAME LAST_NAME  START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- ---------- ---------- --------- --------- ---------- ---------- ---------------
01   Jason      Martin     25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL> SELECT id, first_name, last_name, start_date FROM employee WHERE REGEXP_LIKE(first_name, "^j", "i");
ID   FIRST_NAME LAST_NAME  START_DAT
---- ---------- ---------- ---------
01   Jason      Martin     25-JUL-96
03   James      Smith      12-DEC-78
08   James      Cat        17-SEP-96
SQL> /
ID   FIRST_NAME LAST_NAME  START_DAT
---- ---------- ---------- ---------
01   Jason      Martin     25-JUL-96
03   James      Smith      12-DEC-78
08   James      Cat        17-SEP-96
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>


Using regexp_like(comments, "([[:alnum:]+[:punct:]]+space:+){8,}")

SQL> create table history
  2  ( empno      NUMBER(4)
  3  , beginyear  NUMBER(4)
  4  , begindate  DATE
  5  , enddate    DATE
  6  , deptno     NUMBER(2)
  7  , msal       NUMBER(6,2)
  8  , comments   VARCHAR2(60)
  9  ) ;
Table created.
SQL>
SQL>
SQL>
SQL> insert into history values (9,2000,date "2000-01-01",date "2002-01-02",40, 950,"history for 9");
1 row created.
SQL> insert into history values (8,2000,date "2000-01-02", NULL       ,20, 800,"");
1 row created.
SQL> insert into history values (7,1988,date "2000-01-06",date "2002-01-07",30,1000,"");
1 row created.
SQL> insert into history values (6,1989,date "2000-01-07",date "2002-01-12",30,1300,"");
1 row created.
SQL> insert into history values (5,1993,date "2000-01-12",date "2002-01-10",30,1500,"history for 5");
1 row created.
SQL> insert into history values (4,1995,date "2000-01-10",date "2002-01-11",30,1700,"");
1 row created.
SQL> insert into history values (3,1999,date "2000-01-11", NULL       ,30,1600,"");
1 row created.
SQL> insert into history values (2,1986,date "2000-01-10",date "2002-01-08",20,1000,"history for 2");
1 row created.
SQL> insert into history values (1,1987,date "2000-01-08",date "2002-01-01",30,1000,"history for 1");
1 row created.
SQL> insert into history values (7,1989,date "2000-01-01",date "2002-05-12",30,1150,"history for 7");
1 row created.
SQL>
SQL>
SQL>
SQL> select comments
  2  from   history
  3  where  regexp_like(comments, "([[:alnum:]+[:punct:]]+[[:space:]]+){8,}");
no rows selected
SQL>
SQL> drop table history;
Table dropped.