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What is the ideal data type to use when storing latitude / longitude in a MySQL database?
...culations on lat / long pairs, what datatype is best suited for use with a MySQL database?
21 Answers
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how to concatenate two dictionaries to create a new one in Python? [duplicate]
...ems() for d in (d1, d2, d3)))
and:
from itertools import chain
def dict_union(*args):
return dict(chain.from_iterable(d.items() for d in args))
Python 2.6 & 2.7
from itertools import chain
dict(chain.from_iterable(d.iteritems() for d in (d1, d2, d3))
Output:
>>> from iterto...
Auto Generate Database Diagram MySQL [closed]
...elect specific tables and then create a database diagram for me based on a MySQL database? Preferably it would allow me to edit the diagram afterward since none of the foreign keys are set...
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MySQL - force not to use cache for testing speed of query
I'm testing the speed of some queries in MySQL. The database is caching these queries making it difficult for me to get reliable results when testing how fast these queries are.
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为什么你有10年经验，但成不了专家？ - 杂谈 - 清泛网 - 专注C/C++及内核技术
...有10年经验，但成不了专家？转载自微信公众号李叫兽。如何成为一个领域的专家？有人说主要靠经验，有人说靠天赋，但是大量的研究发现：不论是经验还是天赋，都不是成为...如何成为一个领域的专家？
有人说主要靠经验...
MySQL, Check if a column exists in a table with SQL
I am trying to write a query that will check if a specific table in MySQL has a specific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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Maximum number of records in a MySQL database table
What is the upper limit of records for MySQL database table. I'm wondering about autoincrement field. What would happen if I add milions of records? How to handle this kind of situations?
Thx!
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How do I specify unique constraint for multiple columns in MySQL?
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For those people using MySQL workbench: go to the Indexes tab and select UNIQUE as your type. Give your index a name and check the appropriate columns under the section "Index Columns"
– Pakman
Jun 3 '13 at 2...
“Incorrect string value” when trying to insert UTF-8 into MySQL via JDBC?
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MySQL's utf8 permits only the Unicode characters that can be represented with 3 bytes in UTF-8. Here you have a character that needs 4 bytes: \xF0\x90\x8D\x83 (U+10343 GOTHIC LETTER SAUIL).
If you have MySQL 5.5 or later you...
推动“一带一路”IT产业怎么走 - 资讯 - 清泛网 - 专注C/C++及内核技术
...味着基础设施建设的提速，还有科技和文化的互联互通。如何把握机会借助“一带一路”走出去，如何在IT产业更为发达的地区站稳脚跟并抓住欠发达地区的市场，这成为目前中国IT企业必须解决的问题。“一带一路”倡议对其...