http://sqle.ru/index.php?action=history&feed=atom&title=Oracle_PL%2FSQL%2FPL_SQL%2FConstant_Number
Oracle PL/SQL/PL SQL/Constant Number - История изменений
2026-04-05T20:53:34Z
История изменений этой страницы в вики
MediaWiki 1.30.0
http://sqle.ru/index.php?title=Oracle_PL/SQL/PL_SQL/Constant_Number&diff=1899&oldid=prev
в 13:45, 26 мая 2010
2010-05-26T13:45:19Z
<p></p>
<table class="diff diff-contentalign-left" data-mw="interface">
<tr style="vertical-align: top;" lang="ru">
<td colspan="1" style="background-color: white; color:black; text-align: center;">← Предыдущая</td>
<td colspan="1" style="background-color: white; color:black; text-align: center;">Версия 13:45, 26 мая 2010</td>
</tr><tr><td colspan="2" style="text-align: center;" lang="ru"><div class="mw-diff-empty">(нет различий)</div>
</td></tr></table>
http://sqle.ru/index.php?title=Oracle_PL/SQL/PL_SQL/Constant_Number&diff=1900&oldid=prev
Admin: 1 версия
2010-05-26T09:59:27Z
<p>1 версия</p>
<p><b>Новая страница</b></p><div>==Change constant number==<br />
<br />
<br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="sql"><br />
<br />
SQL><br />
SQL> -- change constant number<br />
SQL><br />
SQL> declare<br />
2 myconstant constant number := 50;<br />
3 begin<br />
4 myconstant := 51;<br />
5 end;<br />
6 /<br />
myconstant := 51;<br />
*<br />
ERROR at line 4:<br />
ORA-06550: line 4, column 5:<br />
PLS-00363: expression "MYCONSTANT" cannot be used as an assignment target<br />
ORA-06550: line 4, column 5:<br />
PL/SQL: Statement ignored<br />
<br />
SQL><br />
<br />
<br />
</source><br />
<br />
<br />
<br />
<br />
==Declare initialized constant number==<br />
<br />
<br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="sql"><br />
<br />
SQL><br />
SQL><br />
SQL><br />
SQL> -- declare initialized constant number<br />
SQL><br />
SQL> declare<br />
2 l_number_constant constant number := 50;<br />
3 begin<br />
4 null;<br />
5 dbms_output.put_line(l_number_constant);<br />
6 end;<br />
7 /<br />
50<br />
PL/SQL procedure successfully completed.<br />
SQL><br />
SQL><br />
<br />
<br />
</source><br />
<br />
<br />
<br />
<br />
==declare number constant uninitialized==<br />
<br />
<br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="sql"><br />
<br />
SQL><br />
SQL> declare<br />
2 myNumber_constant constant number;<br />
3 begin<br />
4 null;<br />
5 end;<br />
6 /<br />
myNumber_constant constant number;<br />
*<br />
ERROR at line 2:<br />
ORA-06550: line 2, column 5:<br />
PLS-00322: declaration of a constant "MYNUMBER_CONSTANT" must contain an initialization assignment<br />
ORA-06550: line 2, column 23:<br />
PL/SQL: Item ignored<br />
<br />
SQL><br />
<br />
</source><br />
<br />
<br />
<br />
<br />
==This script demonstrates constants==<br />
<br />
<br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="sql"><br />
<br />
SQL><br />
SQL><br />
SQL> SET SERVEROUTPUT ON<br />
SQL><br />
SQL><br />
SQL> DECLARE<br />
2 fnameValue CONSTANT VARCHAR2(50) := "Ron";<br />
3 BEGIN<br />
4 fnameValue := "AAA";<br />
5 EXCEPTION<br />
6 WHEN OTHERS<br />
7 THEN<br />
8 DBMS_OUTPUT.PUT_LINE(SQLERRM);<br />
9 END;<br />
10 /<br />
fnameValue := "AAA";<br />
*<br />
ERROR at line 4:<br />
ORA-06550: line 4, column 5:<br />
PLS-00363: expression "FNAMEVALUE" cannot be used as an assignment target<br />
ORA-06550: line 4, column 5:<br />
PL/SQL: Statement ignored<br />
<br />
SQL><br />
<br />
<br />
<br />
</source><br />
<br />
<br />
<br />
<br />
==you must initialize the constant at the time of declaration==<br />
<br />
<br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="sql"><br />
<br />
SQL><br />
SQL><br />
SQL> declare<br />
2 myNumber_constant constant number := 50;<br />
3 begin<br />
4 null;<br />
5 end;<br />
6 /<br />
PL/SQL procedure successfully completed.<br />
SQL><br />
SQL><br />
<br />
</source></div>
Admin