Oracle PL/SQL Tutorial/PL SQL Programming/Raise Exception — различия между версиями

Материал из SQL эксперт
Перейти к: навигация, поиск
м (1 версия)
 
(нет различий)

Текущая версия на 10:08, 26 мая 2010

Avoiding exceptions raised in declaration part and exception handler

SQL> create or replace procedure p_validatezip (i_zipCode VARCHAR2)
  2  is
  3       e_tooShort EXCEPTION;
  4       e_tooLong  EXCEPTION;
  5       e_badZip   EXCEPTION;
  6       pragma exception_init(e_badZip, -20998);
  7       v_tempZip number:=to_number(i_zipCode);
  8  begin
  9       if length(i_zipCode)< 5 then
 10         raise e_tooShort;
 11       elsif  length(i_zipCode)> 6 then
 12         raise e_tooLong;
 13       end if;
 14  exception
 15       when e_tooLong then
 16          DBMS_OUTPUT.put_line("long zip");
 17          raise e_badZip;
 18       when e_tooShort then
 19          DBMS_OUTPUT.put_line("short zip");
 20       when VALUE_ERROR then
 21          DBMS_OUTPUT.put_line("non-numeric zip");
 22          raise e_badZip;
 23    end;
 24  /
Procedure created.
SQL>
SQL> declare
  2
  3  begin
  4      p_validatezip("9123412341234");
  5  end;
  6  /
long zip
declare
*
ERROR at line 1:
ORA-20998:
ORA-06512: at "sqle.P_VALIDATEZIP", line 17
ORA-06510: PL/SQL: unhandled user-defined exception
ORA-06512: at line 4

SQL>


Exceptions Raised in the Exception Handler

SQL>
SQL> create or replace procedure p_validatezip (i_zipCode VARCHAR2)
  2  is
  3       e_tooShort EXCEPTION;
  4       e_tooLong  EXCEPTION;
  5       e_badZip   EXCEPTION;
  6       pragma exception_init(e_badZip, -20998);
  7       v_tempZip NUMBER;
  8  begin
  9       if length(i_zipCode)< 5 then
 10         Raise e_tooShort;
 11       elsif  length(i_zipCode)> 6 then
 12         Raise e_tooLong;
 13       end if;
 14       v_tempZip := to_number(i_zipCode);
 15  exception
 16       when e_tooLong then
 17        raise e_badZip;
 18     when e_tooShort then
 19        raise e_badZip;
 20     when VALUE_ERROR then
 21        raise e_badZip;
 22     when e_badZip then
 23        DBMS_OUTPUT.put_line("problem with Zip");
 24        raise;
 25  end;
 26  /
Procedure created.
SQL> begin
  2      p_validatezip("9406123123");
  3  end;
  4  /
begin
*
ERROR at line 1:
ORA-20998:
ORA-06512: at "sqle.P_VALIDATEZIP", line 17
ORA-06510: PL/SQL: unhandled user-defined exception
ORA-06512: at line 2

SQL>


Propogating a Server-side Customized Error Number and Error Message to client program using PRAGMA EXCEPTION_INIT

SQL>
SQL> create table company(
  2     product_id        number(4)    not null,
  3     company_id          NUMBER(8)    not null,
  4     company_short_name  varchar2(30) not null,
  5     company_long_name   varchar2(60)
  6  );
Table created.
SQL> insert into company values(1,1001,"A Inc.","Long Name A Inc.");
1 row created.
SQL> insert into company values(1,1002,"B Inc.","Long Name B Inc.");
1 row created.
SQL> insert into company values(1,1003,"C Inc.","Long Name C Inc.");
1 row created.
SQL> insert into company values(2,1004,"D Inc.","Long Name D Inc.");
1 row created.
SQL> insert into company values(2,1005,"E Inc.","Long Name E Inc.");
1 row created.
SQL> insert into company values(2,1006,"F Inc.","Long Name F Inc.");
1 row created.
SQL>
SQL>
SQL>
SQL>
SQL> CREATE OR REPLACE PROCEDURE org_proc
  2                  (p_flag_in VARCHAR2,
  3                   p_product_id NUMBER,
  4                   p_company_id NUMBER,
  5                   p_company_short_name VARCHAR2,
  6                   p_company_long_name VARCHAR2)
  7  IS
  8    v_error_code NUMBER;
  9  BEGIN
 10    IF (p_flag_in ="I")THEN
 11      BEGIN
 12        INSERT INTO company VALUES (p_product_id,p_company_id,p_company_short_name,p_company_long_name);
 13      EXCEPTION WHEN OTHERS THEN
 14        v_error_code :=SQLCODE;
 15        IF v_error_code =-1 THEN
 16          RAISE_APPLICATION_ERROR(-20000,"Organization "||
 17          TO_CHAR(p_company_id)||" already exists.");
 18        ELSIF v_error_code =-2291 THEN
 19          RAISE_APPLICATION_ERROR(-20001,"Invalid Hierarchy Code "||
 20          TO_CHAR(p_product_id)||" specified. Cannot create organization.");
 21        END IF;
 22      END;
 23    ELSIF (p_flag_in ="C")THEN
 24      BEGIN
 25        UPDATE company
 26        set company_short_name =p_company_short_name,
 27        company_long_name =p_company_long_name
 28        WHERE product_id =p_product_id
 29        AND company_id =p_company_id;
 30        IF SQL%NOTFOUND THEN
 31          RAISE_APPLICATION_ERROR(-20002,"Organization "||
 32          TO_CHAR(p_company_id)||
 33          " does not exist.");
 34        END IF;
 35      END;
 36    ELSIF (p_flag_in ="D")THEN
 37      BEGIN
 38        DELETE company
 39        WHERE product_id =p_product_id
 40        AND company_id =p_company_id;
 41        IF SQL%NOTFOUND THEN
 42          RAISE_APPLICATION_ERROR(-20003,"Organization "||
 43          TO_CHAR(p_company_id)||
 44          " does not exist. Cannot delete info for the same.");
 45        END IF;
 46      EXCEPTION WHEN OTHERS THEN
 47        v_error_code :=SQLCODE;
 48        IF v_error_code =-2292 THEN
 49          RAISE_APPLICATION_ERROR(-20004,"Organization "||
 50          TO_CHAR(p_company_id)||
 51          " site details defined for it.");
 52        END IF;
 53      END;
 54    END IF;
 55  END;
 56  /
Procedure created.
SQL>
SQL> DECLARE
  2    v_product_id NUMBER := 6;
  3    v_company_id NUMBER := 1010;
  4    v_company_short_name VARCHAR2(30):= "O Inc.";
  5    v_company_long_name VARCHAR2(60):= "O Inc.";
  6    excep1 EXCEPTION;
  7    PRAGMA EXCEPTION_INIT(excep1,-20000);
  8    excep2 EXCEPTION;
  9    PRAGMA EXCEPTION_INIT(excep2,-20001);
 10  BEGIN
 11    org_proc("I",v_product_id,v_company_id,v_company_short_name,v_company_long_name);
 12  EXCEPTION
 13    WHEN excep1 or excep2 THEN
 14      DBMS_OUTPUT.PUT_LINE(SQLERRM);
 15    WHEN OTHERS THEN
 16      DBMS_OUTPUT.PUT_LINE(TO_CHAR(SQLCODE)||SQLERRM);
 17  END;
 18  /
PL/SQL procedure successfully completed.
SQL>
SQL> drop table company;
Table dropped.
SQL>
SQL>


Raise Exception in a function

SQL> set serveroutput on
SQL> DECLARE
  2       quantity1 NUMBER := -2;
  3       quantity2 NUMBER := 3;
  4       total NUMBER := 0;
  5       quantity_must_positive EXCEPTION;
  6       FUNCTION find_cost (quant NUMBER) RETURN NUMBER IS
  7       BEGIN
  8            IF (quant > 0)
  9            THEN
 10                 RETURN(quant * 20);
 11            ELSE
 12                 RAISE quantity_must_positive;
 13            END IF;
 14       END find_cost;
 15  BEGIN
 16       total := find_cost (quantity2);
 17       total := total + find_cost(quantity1);
 18  EXCEPTION
 19       WHEN quantity_must_positive
 20       THEN
 21            dbms_output.put_line("Total until now: " || total);
 22            dbms_output.put_line("Tried to use negative quantity ");
 23  END;
 24  /
Total until now: 60
Tried to use negative quantity
PL/SQL procedure successfully completed.
SQL>
SQL>


Raising a custom exception

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> DECLARE
  2    e_TooManyEmployee EXCEPTION;  -- Exception to indicate an error condition
  3    v_CurrentEmployee NUMBER(3);
  4    v_MaxEmployee NUMBER(3);
  5
  6  BEGIN
  7
  8    v_CurrentEmployee := 5;
  9
 10    SELECT max(id)
 11      INTO v_MaxEmployee
 12      FROM employee;
 13
 14    IF v_CurrentEmployee > v_MaxEmployee THEN
 15      RAISE e_TooManyEmployee;
 16    END IF;
 17  END;
 18  /
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.


Raising an Exception in the Declaration Section

SQL> create or replace procedure p_validatezip (i_zipCode VARCHAR2)
  2  is
  3       e_tooShort EXCEPTION;
  4       e_tooLong  EXCEPTION;
  5       e_badZip   EXCEPTION;
  6       pragma exception_init(e_badZip, -20998);
  7       v_tempZip number:=to_number(i_zipCode);
  8  begin
  9       if length(i_zipCode)< 5 then
 10         raise e_tooShort;
 11       elsif  length(i_zipCode)> 6 then
 12         raise e_tooLong;
 13       end if;
 14  exception
 15       when e_tooLong then
 16          DBMS_OUTPUT.put_line("long zip");
 17          raise e_badZip;
 18       when e_tooShort then
 19          DBMS_OUTPUT.put_line("short zip");
 20       when VALUE_ERROR then
 21          DBMS_OUTPUT.put_line("non-numeric zip");
 22          raise e_badZip;
 23    end;
 24  /
Procedure created.
SQL>
SQL> declare
  2
  3  begin
  4      p_validatezip("9123412341234");
  5  end;
  6  /
long zip
declare
*
ERROR at line 1:
ORA-20998:
ORA-06512: at "sqle.P_VALIDATEZIP", line 17
ORA-06510: PL/SQL: unhandled user-defined exception
ORA-06512: at line 4

SQL>


Raising an Exception Local PL/SQL Block

SQL> --
SQL>
SQL>
SQL> create or replace function f_get_speed(i_distance NUMBER, i_timeSec NUMBER)
  2  return NUMBER
  3  is
  4    v_out NUMBER;
  5  begin
  6
  7    begin
  8      v_out:= i_distance/i_timeSec;
  9    exception
 10        when zero_divide then
 11        DBMS_OUTPUT.put_line("Divide by zero in the F_GET_SPEED");
 12    end;
 13    return v_out;
 14  end;
 15  /
Function created.
SQL>
SQL> select f_get_speed(1, 0) from dual;
F_GET_SPEED(1,0)
----------------

Divide by zero in the F_GET_SPEED
SQL>


Raising NO_DATA_FOUND

SQL>
SQL> DECLARE
  2    TYPE t_NumberTableType IS TABLE OF NUMBER
  3      INDEX BY BINARY_INTEGER;
  4    v_NumberTable t_NumberTableType;
  5    v_TempVar NUMBER;
  6  BEGIN
  7    v_TempVar := v_NumberTable(1);
  8  END;
  9  /
DECLARE
*
ERROR at line 1:
ORA-01403: no data found
ORA-06512: at line 7

SQL>
SQL>


User-Defined Errors

Users can explicitly raise an exception with the RAISE command.

Steps for trapping a user-defined error include the following:

Declare the name for the user exception within the declaration section of the block.

Raise the exception explicitly within the executable portion of the block using the RAISE command.

Reference the declared exception with an error-handling routine.

24. 16. Raise Exception 24. 16. 1. User-Defined Errors 24. 16. 2. <A href="/Tutorial/Oracle/0480__PL-SQL-Programming/RaiseExceptioninafunction.htm">Raise Exception in a function</a> 24. 16. 3. <A href="/Tutorial/Oracle/0480__PL-SQL-Programming/RaisinganExceptionLocalPLSQLBlock.htm">Raising an Exception Local PL/SQL Block</a> 24. 16. 4. <A href="/Tutorial/Oracle/0480__PL-SQL-Programming/Avoidingexceptionsraisedindeclarationpartandexceptionhandler.htm">Avoiding exceptions raised in declaration part and exception handler</a> 24. 16. 5. <A href="/Tutorial/Oracle/0480__PL-SQL-Programming/RaisinganExceptionintheDeclarationSection.htm">Raising an Exception in the Declaration Section</a> 24. 16. 6. <A href="/Tutorial/Oracle/0480__PL-SQL-Programming/ExceptionsRaisedintheExceptionHandler.htm">Exceptions Raised in the Exception Handler</a> 24. 16. 7. <A href="/Tutorial/Oracle/0480__PL-SQL-Programming/RaisingNODATAFOUND.htm">Raising NO_DATA_FOUND</a> 24. 16. 8. <A href="/Tutorial/Oracle/0480__PL-SQL-Programming/Raisingacustomexception.htm">Raising a custom exception</a> 24. 16. 9. <A href="/Tutorial/Oracle/0480__PL-SQL-Programming/UsingWHENOTHERSclause.htm">Using WHEN OTHERS clause</a> 24. 16. 10. <A href="/Tutorial/Oracle/0480__PL-SQL-Programming/UsingSQLCODEandSQLERRM.htm">Using SQLCODE and SQLERRM</a> 24. 16. 11. <A href="/Tutorial/Oracle/0480__PL-SQL-Programming/PropogatingaServersideCustomizedErrorNumberandErrorMessagetoclientprogramusingPRAGMAEXCEPTIONINIT.htm">Propogating a Server-side Customized Error Number and Error Message to client program using PRAGMA EXCEPTION_INIT</a>

Using SQLCODE and SQLERRM

SQL> create table product(
  2     product_id number(4)     not null,
  3     product_description varchar2(20) not null
  4  );
Table created.
SQL>
SQL> insert into product values (1,"Java");
1 row created.
SQL> insert into product values (2,"Oracle");
1 row created.
SQL> insert into product values (3,"C#");
1 row created.
SQL> insert into product values (4,"Javascript");
1 row created.
SQL> insert into product values (5,"Python");
1 row created.
SQL>
SQL>
SQL> DECLARE
  2    v_descr VARCHAR2(20);
  3  BEGIN
  4    SELECT product_description
  5    INTO v_descr
  6    FROM product
  7    WHERE product_id =10;
  8    dbms_output.put_line(v_descr);
  9  EXCEPTION
 10    WHEN NO_DATA_FOUND THEN
 11    dbms_output.put_line("ERR:Invalid Hierarchy Code 10");
 12    WHEN OTHERS THEN
 13      dbms_output.put_line("ERR:An error occurred with info :"||
 14      TO_CHAR(SQLCODE)||" "||SQLERRM);
 15  END;
 16  /
ERR:Invalid Hierarchy Code 10
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL> drop table product;
Table dropped.
SQL>


Using WHEN OTHERS clause

SQL> create table product(
  2     product_id number(4)     not null,
  3     product_description varchar2(20) not null
  4  );
Table created.
SQL>
SQL> insert into product values (1,"Java");
1 row created.
SQL> insert into product values (2,"Oracle");
1 row created.
SQL> insert into product values (3,"C#");
1 row created.
SQL> insert into product values (4,"Javascript");
1 row created.
SQL> insert into product values (5,"Python");
1 row created.
SQL>
SQL>
SQL> DECLARE
  2    v_descr VARCHAR2(20);
  3  BEGIN
  4    SELECT product_description
  5    INTO v_descr
  6    FROM product
  7    WHERE product_id =10;
  8    dbms_output.put_line(v_descr);
  9  EXCEPTION WHEN OTHERS THEN
 10    dbms_output.put_line("ERR:Invalid Hierarchy Code 10");
 11  END;
 12  /
ERR:Invalid Hierarchy Code 10
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL>
SQL> drop table product;
Table dropped.
SQL>