http://blog.sina.com.cn/s/blog_61c006ea0100m2uo.html

1、create table testd(id int,name char(5));

begin
for i in 1..1000000 loop
    insert into testd values(
       i,to_char(dbms_random.random()));
end loop;
commit;
end;
/

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ERROR at line 1:
ORA-12899: value too large for column "BREIN"."TESTA"."NAME"(actual: 9,maximum: 5)
ORA-06512: at line 3

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  原因为name的字段宽度太小了

begin
for i in 1..3 loop
    insert into testd values(
       i,to_char(dbms_random.random()));
end loop;
commit;
end;
/

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ERROR at line 1:
ORA-12899: value too large for column "BREIN"."TESTA"."NAME"(actual: 9,maximum: 5)
ORA-06512: at line 3

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还报同样的错误。

2、create table testd(id int,name char(500));

begin
for i in 1..1000000 loop
    insert into testd values(
       i,to_char(dbms_random.random()));
end loop;
commit;
end;
/

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PL/sql procedure successfully completed.

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3、create table testd(id int,name varchar2(20),addrvarchar2(20),dele varchar2(20),modi varchar2(20));

begin
for i in 1..1000000 loop
    insert into testd values(
       i,to_char(dbms_random.random()),
dbms_random.random(),dbms_random.random(),
to_char(dbms_random.random()));
end loop;
commit;
end;
/

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PL/sql procedure successfully completed.

原来int型的可以默认插入字符型字段中去

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