json_extract is a function for extract data from a JSON document both in MySQL and MariaDB. The function normally works fine, for example 1set @j = '{"num": 42, "list": [1, 2, 3], "obj": {"name": "Edward Stark"}}'; 2select json_extract(@j, '$.num') as num, json_extract(@j, '$.list') as list, json_extract(@j, '$.obj') …

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Here in the post, I will share some examples about the contextvars (new in Python 3.7) and thread local. Default Value In the module level, use ContextVar.set or directly setattr for a thread local variable, won't successfully set a default value, the value set won't take effect in another thread. To ensure a default …

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During the 2018 Chinese National Day Holidays, Bloomberg Business Week reported that Chinese hackers planted microchips into motherboards supplying for data center servers of tech giants Apple and Amazon. The original Bloomberg post is available at …

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The metaphor Ponzi Software Development Scheme, came to me after I have been read about a post from CACM, The Death of Big Software. The traditional big softwares will die away, because they are easily growing to become too hard to maintain, and will be replaced by cloud or microservices architecture based softwares. …

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Since Mongodb 3.2 and MongoEngine 0.9, we can use $aggregate command to perform join queries on multiple collections in a database. This post would be a simple tutorial for join queries on Mongodb(via MongoEngine in Python) with examples. Models Setup Let's consider models defined as below: 1import random 2import …

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