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Storing JSON in database vs. having a new column for each key
...figured it was worth an update.
When this question was originally posted, MySQL had no support for JSON data types and the support in PostgreSQL was in its infancy. Since 5.7, MySQL now supports a JSON data type (in a binary storage format), and PostgreSQL JSONB has matured significantly. Both prod...
How to properly create composite primary keys - MYSQL
...ep these as two distinct columns. You could use a two-column primay key in mysql ...PRIMARY KEY(id_a, id_b)... but I prefer using a two-column unique index, and having an auto-increment primary key field.
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Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
Is there a Boolean data type in Microsoft SQL Server like there is in MySQL?
9 Answers
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How to convert SQL Query result to PANDAS Data Structure?
...Original answer:
I can't help you with SQLAlchemy -- I always use pyodbc, MySQLdb, or psychopg2 as needed. But when doing so, a function as simple as the one below tends to suit my needs:
import decimal
import pydobc
import numpy as np
import pandas
cnn, cur = myConnectToDBfunction()
cmd = "SELE...
Return rows in random order [duplicate]
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For MySQL use ORDER BY uuid(). (...for those arriving on this page via a generic search, like me!)
– Stan James
Jan 7 '12 at 4:15
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浅谈TCP优化 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...里就不一一说明了，有兴趣的读者可以自行查阅。
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如何调整「rwnd」到一个合理值
有很多人都遇到过网络传输速度过慢的问题，比如说明明是百兆网络，其最大传输数据的理论值怎么着也得有个十兆，但是实际情况却相距...
GROUP_CONCAT comma separator - MySQL
...f%2fstackoverflow.com%2fquestions%2f7691816%2fgroup-concat-comma-separator-mysql%23new-answer', 'question_page');
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How to use GROUP_CONCAT in a CONCAT in MySQL
If I have a table with the following data in MySQL:
7 Answers
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MySQL CONCAT returns NULL if any field contain NULL
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mysql has IFNULL(arg, default) instead COALESCE with the same syntax
– Vasilii Suricov
Feb 19 '19 at 17:58
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Count table rows
What is the MySQL command to retrieve the count of records in a table?
11 Answers
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