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SQLPLUS »·¾³ÓÃsubstitution variables ºÍ host(bind) variable À´´«ÈëÊýÖµ¸øPL/SQL¿é
substitution variable: such as a preceding ampersand &a
host(bind) variable : such as a preceding colon :x
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SQL> var df df
Usage: VAR[IABLE] [ <variable> [ NUMBER | CHAR | CHAR (n [CHAR|BYTE]) |
VARCHAR2 (n [CHAR|BYTE]) | NCHAR | NCHAR (n) |
NVARCHAR2 (n) | CLOB | NCLOB | REFCURSOR |
BINARY_FLOAT | BINARY_DOUBLE ] ]
SQL> var a number
SQL> exec :a :=123
PL/SQL procedure successfully completed.
SQL> edit
Wrote file afiedt.buf
1 declare
2 begin
3 dbms_output.put_line('result='||'&a'||:a);
4* end;
SQL> /
Enter value for a: i love u
old 3: dbms_output.put_line('result='||'&a'||:a);
new 3: dbms_output.put_line('result='||'i love u'||:a);
result=i love u123
PL/SQL procedure successfully completed.
SQL>
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