Re: [HACKERS] The question about the type numeric
I am so sorry for that. This is my fault. My mail client does not receive any e-mail. So I tried to re-send the e-mail again. My problem has been resolved. Thank you for your reply. 2014-04-16 wangshuo HighGo Software Co.,Ltd. Address: A203 Block D QILU Soft Park, High-Tech Zone, Lixia district, Jinan Shandong, China(Head Office) Tel:+86-0531-55701530 Fax:+86-0531-55701544 Website：www.highgo.com Mobile：18766416137 发件人：David G Johnston david.g.johns...@gmail.com 发送时间：2014-04-16 10:23 主题：Re: [HACKERS] The question about the type numeric 收件人：pgsql-hackerspgsql-hackers@postgresql.org 抄送： sure.postgres wrote Hi hackers, I am learning about numeric . The comment of NumericShort format is: * In the NumericShort format, the remaining 14 bits of the header word * (n_short.n_header) are allocated as follows: 1 for sign (positive or * negative), 6 for dynamic scale, and 7 for weight. In practice, most * commonly-encountered values can be represented this way. So the Max of the NumericShort format should be up to 508 digits before the decimal point. So the sign of the number 12345678901234567890123456789012345678901234567890 12345678901234567890123456789012345678901234567890123456789012345678901234567890 12345678901234567890123456789012345678901234567890123456789012345678901234567890 12345678901234567890123456789012345678901234567 should be 0x807F. The number is 257 digits before the decimal point. But the sign is 0. So is there anything wrong? [1000 00][0][00111 0][001] I appreciate that you got no responses on the original e-mail but if you are going to re-raise the question at least have the courtesy to respond to your original thread and not go and start a new one. And maybe trying rephrasing the question since most likely your original question was not worded in such a way to garner a response. I may have this totally wrong but I don't see why the sign of your number should be anything but zero since that is, I presume, the value of the specific bit for a positive number - which yours is. So, in short, nothing seems to be wrong. If you think something is wrong you should probably state what that is explicitly and ask someone to explain what is happening. I would have said all this when I saw the first e-mail but I wasn't (and still am not) totally clear on what you are asking and was hoping someone more familiar could make better sense of it. David J. -- View this message in context: http://postgresql.1045698.n5.nabble.com/The-question-about-the-type-numeric-tp5800173p5800174.html Sent from the PostgreSQL - hackers mailing list archive at Nabble.com. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] The question about the type numeric
But the sign is 0. So is there anything wrong? have look in src/backend/utils/adt/numeric.c @ 154 155 for POS NEG defination given as 154 #define NUMERIC_POS 0x 155 #define NUMERIC_NEG 0x4000 Regards, Amul Sul -- View this message in context: http://postgresql.1045698.n5.nabble.com/The-question-about-the-type-numeric-tp5800180p5800219.html Sent from the PostgreSQL - hackers mailing list archive at Nabble.com. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] The question about the type numeric
On Tue, Apr 15, 2014 at 5:37 AM, sure.postgres sure.postg...@gmail.com wrote: Hi hackers, I am learning about numeric . The comment of NumericShort format is: * In the NumericShort format, the remaining 14 bits of the header word * (n_short.n_header) are allocated as follows: 1 for sign (positive or * negative), 6 for dynamic scale, and 7 for weight. In practice, most * commonly-encountered values can be represented this way. So the Max of the NumericShort format should be up to 508 digits before the decimal point. So the sign of the number 12345678901234567890123456789012345678901234567890 12345678901234567890123456789012345678901234567890123456789012345678901234567890 12345678901234567890123456789012345678901234567890123456789012345678901234567890 12345678901234567890123456789012345678901234567 should be 0x807F. The number is 257 digits before the decimal point. But the sign is 0. So is there anything wrong? I'm not sure I understand the question, but if it helps, the sign bit will be set (1) for negative values and clear (0) for positive values. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] The question about the type numeric
sure.postgres wrote Hi hackers, I am learning about numeric . The comment of NumericShort format is: * In the NumericShort format, the remaining 14 bits of the header word * (n_short.n_header) are allocated as follows: 1 for sign (positive or * negative), 6 for dynamic scale, and 7 for weight. In practice, most * commonly-encountered values can be represented this way. So the Max of the NumericShort format should be up to 508 digits before the decimal point. So the sign of the number 12345678901234567890123456789012345678901234567890 12345678901234567890123456789012345678901234567890123456789012345678901234567890 12345678901234567890123456789012345678901234567890123456789012345678901234567890 12345678901234567890123456789012345678901234567 should be 0x807F. The number is 257 digits before the decimal point. But the sign is 0. So is there anything wrong? [1000 00][0][00111 0][001] I appreciate that you got no responses on the original e-mail but if you are going to re-raise the question at least have the courtesy to respond to your original thread and not go and start a new one. And maybe trying rephrasing the question since most likely your original question was not worded in such a way to garner a response. I may have this totally wrong but I don't see why the sign of your number should be anything but zero since that is, I presume, the value of the specific bit for a positive number - which yours is. So, in short, nothing seems to be wrong. If you think something is wrong you should probably state what that is explicitly and ask someone to explain what is happening. I would have said all this when I saw the first e-mail but I wasn't (and still am not) totally clear on what you are asking and was hoping someone more familiar could make better sense of it. David J. -- View this message in context: http://postgresql.1045698.n5.nabble.com/The-question-about-the-type-numeric-tp5800173p5800174.html Sent from the PostgreSQL - hackers mailing list archive at Nabble.com. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
