用于PK的数据类型是什么？ [英] What datatype to use for PK?
问题描述
多年来，我一直使用小数（18,0）作为
主键的数据类型。除了涉及的重要数字的数量，
BigInt类型的性能会更好，或者十进制（18,0）仍然可以。
-
Don Vaillancourt
软件开发总监
WEB IMPACT INC。
电话：416-815-2000转。 245
传真：416-815-2001
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Over the years I have always used the decimal(18,0) as the datatype for
primary keys. Aside from the number of significant numbers involved,
would BigInt type be better for performance or is decimal(18,0) still okay.
--
Don Vaillancourt
Director of Software Development
WEB IMPACT INC.
phone: 416-815-2000 ext. 245
fax: 416-815-2001
email: do**@web-impact.com <mailto:do**@webimpact.com>
web: http://www.web-impact.com
Web Impact Inc. <http://www.web-impact.com>
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推荐答案
BIGINT比DECIMAL小一个字节（ 18,0）。 8字节与9
字节。
除非你在说话，否则不太可能显着改变性能
百万行正在处理。
BIGINT is stored one byte smaller than DECIMAL(18,0). 8 bytes vs. 9
bytes.
Not likely to significantly change performance unless you''re talking
millions of rows being processed.
我一直认为小数以文本格式存储它的值。因此，对于
十进制（18,0），MSSQL将占用18个字节。或者我部分正确并且
MSSQL使用半字节来表示数字。
Gary写道：
I always thought that decimal stored it''s values in text format. So for
decimal(18,0) MSSQL would take up 18 bytes. Or am I partially right and
MSSQL uses a nibble to represent a digit.
Gary wrote:
BIGINT存储一个字节小于DECIMAL（18,0）。 8字节与9
字节。
除非您正在谈论数百万行正在处理，否则不太可能显着改变性能。
BIGINT is stored one byte smaller than DECIMAL(18,0). 8 bytes vs. 9
bytes.
Not likely to significantly change performance unless you''re talking
millions of rows being processed.
-
Don Vaillancourt
软件开发总监
WEB IMPACT INC。
电话：416 -815-2000分机245
传真：416-815-2001
电子邮件：执行** @ web- impact.com < mailto：do ** @ webimpact.com>
web： http://www.web-impact.com
Web Impact Inc.< http://www.web-impact.com>
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，并且是收件人的责任。
--
Don Vaillancourt
Director of Software Development
WEB IMPACT INC.
phone: 416-815-2000 ext. 245
fax: 416-815-2001
email: do**@web-impact.com <mailto:do**@webimpact.com>
web: http://www.web-impact.com
Web Impact Inc. <http://www.web-impact.com>
This email message is intended only for the addressee(s) and contains
information that may be confidential and/or copyright.
If you are not the intended recipient please notify the sender by reply
email and immediately delete this email.
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intended recipient(s) is strictly prohibited. No representation is made
that this email or any attachments are free of viruses. Virus scanning
is recommended and is the responsibility of the recipient.
这是不正确的。 DECIMAL（18,0）使用以十六进制格式存储的9个字节
格式，而不是文本格式。检查BOL。
That is not correct. DECIMAL (18,0) uses 9 bytes stored in hexadecimal
format, not text format. Check BOL.
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