MySQL Postgres list databases SHOW DATABASES \l change to a database USE <db_name> \c <db_name> list tables SHOW TABLES \dt describe a table DESC <table_name> \d <table_name> show the create table sql SHOW CREATE TABLE <table_name> pg_dump -st <table_name> <db_name> explain a query EXPLAIN <sql_statement> EXPLAIN …

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We can simply start the Next.js application using next start. However, when facing higher traffic demands in practical use, how can we deploy Next.js using a multi-process approach? We can achieve this using the cluster mode of pm2. The cluster mode is a powerful way of scaling Node.js applications, allowing you to …

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python -m http.server is a very convenient command line tool to start an ad-hoc static web server. This tool is very useful when you want to develop small web applications or serve static files. But it does not support SSL. A lot of modern web applications as well as browser features require a secured connection. So I …

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In Python, the contextvars is somehow like thread local, but mostly for coroutines. But will the context itself be kept consistent in a chain of asyncio tasks? Let's find out. contextvars Let's have a rough review of the contextvars in Python. The contextvars module provides a way to maintain a context across a chain …

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WSL is good, it will be even better if we can pipe stdout directly into Windows host’s clipboard. Just like 1 ./myscript.sh | to-my-clipboard.sh Note that xclip requires X, so it is not an option. From WSL, we have direct access to Windows executables. The easiest method would be using clip.exe: 1 ./myscript.sh | …

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After enrolled for Python in Excel preview, now I can type =py( in any Excel cell to write some Python code. Python in Excel doesn't have detailed documents, only Get Started tutorials, like link 1, link 2, or articles talking about topics like pandas, matplotlib, seaborn, etc., it may confuse you when you want to do …

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If haven't searched both "python" and "robots.txt" in the same input box, I would not ever know that Python Standard Library could parse robots.txt with urllib.robotparser. But the official document of urllib.robotparser doesn't go into detail. With the document, you could check whether a url can be fetch with a robot …

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Pipelining streamed data events directly into Amazon S3 via the AWS Kinesis Firehose service is convenient and efficient. And we could use Python with boto3 to consume the data directly from S3. This allows for seamless storage of your data, ensuring its integration and accessibility. Mostly, we are dealing with …

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Nowadays, as it pleased most frontend engineers, making web pages/applications compatible with IE Browser is not required almost everywhere. Internet Explorer, especially the lower versions, is inconsistent with W3C standards, barely has developer toolchains, and therefore very hard to debug. But the anti-modern …

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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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