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Create boolean column in MySQL with false as default value?
I want to create a table in MySQL with a boolean column whose default value is false . But it's accepting NULL as default...
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MySQL error: key specification without a key length
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The error happens because MySQL can index only the first N chars of a BLOB or TEXT column. So The error mainly happens when there is a field/column type of TEXT or BLOB or those belong to TEXT or BLOB types such as TINYBLOB, MEDIUMBLOB, LONGBLOB, TINY...
When should I use Kruskal as opposed to Prim (and vice versa)?
...c.
If you implement both Kruskal and Prim, in their optimal form : with a union find and a finbonacci heap respectively, then you will note how Kruskal is easy to implement compared to Prim.
Prim is harder with a fibonacci heap mainly because you have to maintain a book-keeping table to record the...
What do column flags mean in MySQL Workbench?
In MySQL Workbench table editor there are 7 column flags available: PK, NN, UQ, BIN, UN, ZF, AI.
3 Answers
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How do I add indices to MySQL tables?
I've got a very large MySQL table with about 150,000 rows of data. Currently, when I try and run
7 Answers
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编程基础与事件状态 06：把任务与记录保存下来 · App Inventor 2 中文网
...120秒。
延迟回调按实际时间计算。
运行中重复开始不重置。
重启读取设置、记录和暂停快照。
暂停期间不扣时。
完成记录持久化。
到期与重复计时回调。
排查时先确定出错的是输入、状态、数据读取还是显示；用...
新浪是如何分析处理32亿条实时日志的？ - 更多技术 - 清泛网 - 专注C/C++及内核技术
新浪是如何分析处理32亿条实时日志的？【编者的话】我从2014年初入职新浪后就开始接触实时日志分析相关的技术，主要是ELK（Elasticsearch、Logstash、Kibana），当时是学习+ELK优...【编者的话】我从2014年初入职新浪后就开始接触实...
“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
... but the values you insert don't map to a partition.
If you use REPLACE, MySQL actually does a DELETE followed by an INSERT internally, which has some unexpected side effects:
A new auto-increment ID is allocated.
Dependent rows with foreign keys may be deleted (if you use cascading foreign ke...
Build an ASCII chart of the most commonly used words in a given text [closed]
...umn FROM OPENROWSET(BULK'A',
SINGLE_BLOB)x;WITH N AS(SELECT 1 i,LEFT(@,1)L UNION ALL SELECT i+1,SUBSTRING
(@,i+1,1)FROM N WHERE i<LEN(@))SELECT i,L,i-RANK()OVER(ORDER BY i)R INTO #D
FROM N WHERE L LIKE'[A-Z]'OPTION(MAXRECURSION 0)SELECT TOP 22 W,-COUNT(*)C
INTO # FROM(SELECT DISTINCT R,(SELECT''+...
Installing specific package versions with pip
I'm trying to install version 1.2.2 of the MySQL_python adaptor, using a fresh virtualenv created with the --no-site-packages option. The current version shown in PyPi is 1.2.3 . Is there a way to install the older version? I found an article stating that this should do it:
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