5. unDumpNumber if Bytes(0) = 128 then --128表示0 result := 0;elsif Bytes(0) > 128 then --大于128表示正数for i in 1 .. vlength - 1 loop result := result + (Bytes(i) - 1) * power(100, (Bytes(0) - 193) - i+1); end loop; else --小于128表示负数for i in 1 .. vlength - 2 loop --负数的最后一个字节总是102，所以可以忽略result := result + (Bytes(i) - 101) * power(100, (62 - Bytes(0)) - i+1); end loop; end if; return(Result);
31. BFILEcreate or replace directory MY_DIR as 'e:/download‘;create table t(c_bfilebfile);insert into t values(bfilename('MY_DIR','Version.xml'));BFILE不是读一致性BFILE在数据库中占用的空间是文件名长度
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