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MySQL: Large VARCHAR vs. TEXT?
I've got a messages table in MySQL which records messages between users. Apart from the typical ids and message types (all integer types) I need to save the actual message text as either VARCHAR or TEXT. I'm setting a front-end limit of 3000 characters which means the messages would never be inserte...
MySQL select one column DISTINCT, with corresponding other columns
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@Full Decent you can't, according to MySQL documentation: "The server is free to choose any value from each group, so unless they are the same, the values chosen are indeterminate.". In practice I've successfully used this kind of queries with ORDER BY clause, ...
python-pandas and databases like mysql
...ing a DBI compatible library. We can look at two short examples using the MySQLdb and cx_Oracle libraries to connect to Oracle and MySQL and query their data dictionaries. Here is the example for cx_Oracle:
import pandas as pd
import cx_Oracle
ora_conn = cx_Oracle.connect('your_connection_string'...
ERROR: Error 1005: Can't create table (errno: 121)
I have troubles with forward engineering my MySQL database into WAMP server..
I was going to post an image of the schema but as this is my first post I can't.
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MySQL Conditional Insert
...his, dual is a table with one row only (found originally in Oracle, now in mysql too). The logic is that the SELECT statement generates a single row of data with the required values, but only when the values are not already found.
Alternatively, look at the MERGE statement.
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30岁之后，程序员该向什么方向发展？ - 杂谈 - 清泛网 - 专注C/C++及内核技术
...怕什么？
QA&3. 专注coding还是走向管理，程序员职场规划如何抉择？
严清：
我是选择了偏向 coding，但还是要做一定管理，我要带领小伙伴们提升技术，要推进公司的技术水平，这些还是需要管理的。可以说是管理技术不管产...
MFC中ComboBox控件的使用 - C/C++ - 清泛网 - 专注C/C++及内核技术
MFC中ComboBox控件的使用一、如何添加 删除Combo Box内容1，在ComboBox控件属性的Data标签里面添加，一行表示ComboBox下拉列表中的一行。换行用ctrl+回车。2，在程...一、如何添加/删除Combo Box内容
1，在ComboBox控件属性的Data标签里面添...
How to do a regular expression replace in MySQL?
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With MySQL 8.0+ you could use natively REGEXP_REPLACE function.
12.5.2 Regular Expressions:
REGEXP_REPLACE(expr, pat, repl[, pos[, occurrence[, match_type]]])
Replaces occurrences in the string expr that match the regular express...
MySQL and GROUP_CONCAT() maximum length
I'm using GROUP_CONCAT() in a MySQL query to convert multiple rows into a single string.
However, the maximum length of the result of this function is 1024 characters.
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Does MySQL index foreign key columns automatically?
Does MySQL index foreign key columns automatically?
9 Answers
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