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Is there a MySQL command to convert a string to lowercase?
I have a MySQL database of keywords that are presently mixed-case. However, I want to convert them all to lowercase. Is there an easy command to do this, either using MySQL or MySQL and PHP?
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MySQL: Fastest way to count number of rows
Which way to count a number of rows should be faster in MySQL?
12 Answers
12
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Delete all Duplicate Rows except for One in MySQL? [duplicate]
How would I delete all duplicate data from a MySQL Table?
2 Answers
2
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Include all existing fields and add new fields to document
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You can use $$ROOT to references the root document. Keep all fields of this document in a field and try to get it after that (depending on your client system: Java, C++, ...)
[
{
$project: {
custom_field: "$obj.ob...
How do I change the data type for a column in MySQL?
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http://dev.mysql.com/doc/refman/5.1/en/alter-table.html
ALTER TABLE tablename MODIFY columnname INTEGER;
This will change the datatype of given column
Depending on how many columns you wish to modify it might be best to generate a scri...
How to pass arguments to a Button command in Tkinter?
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Example GUI:
Let's say I have the GUI:
import tkinter as tk
root = tk.Tk()
btn = tk.Button(root, text="Press")
btn.pack()
root.mainloop()
What Happens When a Button Is Pressed
See that when btn is pressed it calls its own function which is very similar to button_press_handle in t...
How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
...SERT a row when it does not exist, or to UPDATE if it exists, using one MySQL query?
2 Answers
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MySQL Creating tables with Foreign Keys giving errno: 150
I am trying to create a table in MySQL with two foreign keys, which reference the primary keys in 2 other tables, but I am getting an errno: 150 error and it will not create the table.
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Change One Cell's Data in mysql
How can I change the data in only one cell of a mysql table.
I have problem with UPDATE because it makes all the parameters in a column change but I want only one changed. How?
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从Code Review 谈如何做技术这两天，在微博上表达了一下Code Review的重要性。因为翻看了阿里内部的Review Board上的记录，从上面发现Code Review做得好的是一些比...这两天，在微博上表达了一下Code Review的重要性。因为翻看了阿里内部...