Oracle PL/SQL/Char Functions/TRIM

Characters rather than spaces are trimmed

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SQL> -- Characters rather than spaces are trimmed
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SQL>
SQL>
SQL> SELECT TRIM("F" from "Frogs prefer deep water") FROM dual;
TRIM("F"FROM"FROGSPREF
----------------------
rogs prefer deep water
SQL>

LEADING: trim from the beginning of a string

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SQL> -- TRIM "LEADING"
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SQL> SELECT TRIM(LEADING "S" FROM "STEVENS" ) AS TRIM FROM Dual;
TRIM
------
TEVENS
SQL>

Nesting TRIM function

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SQL> SELECT TRIM(TRIM (both "z" from "zzzzz I am asleep zzzzzz")) FROM dual;
TRIM(TRIM(B
-----------
I am asleep
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SQL>

Simple demo for TRIM function: removes all specified characters either from the beginning or the ending of a string

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SQL> --For example, the following query removes the character "S" from a string:
SQL>
SQL> SELECT TRIM("S" FROM "STEVENS") AS TRIM FROM Dual;
TRIM
-----
TEVEN
SQL>

TRAILING: trim from the end of a string

SQL>
SQL> -- TRIM "TRAILING"
SQL>
SQL> SELECT TRIM(TRAILING "S" FROM "STEVENS" ) AS TRIM FROM Dual;
TRIM
------
STEVEN
SQL>

TRIM from both sides

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SQL>
SQL> SELECT TRIM (both " " from " String with blanks ") FROM dual;
TRIM(BOTH""FROM"ST
------------------
String with blanks
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TRIM Leading and Trailing Zeroes

 
SQL> SELECT TRIM (0 FROM 067270676800) "TRIM Example"
  2  FROM DUAL;
TRIM Exam
---------
672706768
1 row selected.
SQL> --

TRIM: removes leading and trailing characters from a string

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>
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SQL>
SQL> -- TRIM: removes leading and trailing characters from a string.
SQL>
SQL> -- TRIM([{LEADING | TRAILING | BOTH}]char FROM string)
SQL>
SQL> select TRIM(First_Name) from employee;
TRIM(FIRST
----------
Jason
Alison
James
Celia
Robert
Linda
David
James
8 rows selected.
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>
SQL>

Trim space from a string

 
SQL>
SQL>  select """ || trim( " " from "   This is a string    " ) || """ "Result"
  2      from dual
  3    /
Result
------------------
"This is a string"
1 row selected.
SQL> --

TRIM(TRAILING "A" FROM "ABCA") trail

 
SQL>
SQL> SELECT
  2     TRIM("A" FROM "ABCA")     both,
  3     TRIM(LEADING  "A" FROM "ABCA")     lead,
  4     TRIM(TRAILING "A" FROM "ABCA")     trail,
  5     TRIM(" ABC ")      blank
  6  FROM dual;
BO LEA TRA BLA
-- --- --- ---
BC BCA ABC ABC
SQL>

Trim trailing space from a string

 
SQL>
SQL> select trim( trailing " " from "This is a string     " ) "Result"
  2  from dual
  3  /
Result
----------------
This is a string
1 row selected.
SQL>
SQL> --