7 and can I work with this table but already on new device with MySQL 8?

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MasterZiv 2021-08-24 14:26:11
Manjunath Dharmatti 2021-08-24 14:13:55
Pls suggest training videos for learning SQL. I am a beginner.

Read books, Martin Gruber, Introduction to SQL

Ishu Gupta 2021-08-24 19:38:21
How can I take database backup of around 1TB size In MySQL without using mysqldump utility
svart 2021-08-24 20:03:00
innobackupex, mariabackup depends on your mysql vendor
yolo_xxi 2021-08-25 16:32:58
mysql_en-12301.jpg
Hi guys, need some help here,.my system kinda slow to connection to database. how to eliminate some of the sleep connection? is this the cause of the slow loading at the system?
Mohammad1_313 2021-08-25 21:07:31
mysql_en-12305.jpg
Hi
i have a question about below example
i wanna know is there any reason why in below example they create seperate table for Category
why dont they add a Category column to question table instead?
svart 2021-08-26 00:01:25
Mohammad1_313 2021-08-25 21:07:31
Hi
i have a question about below example
i wanna know is there any reason why in below example they create seperate table for Category
why dont they add a Category column to question table instead?

you’d better ask them

svart 2021-08-26 00:03:15
yolo_xxi 2021-08-25 16:32:58
Hi guys, need some help here,.my system kinda slow to connection to database. how to eliminate some of the sleep connection? is this the cause of the slow loading at the system?

looks like you have idle connections or connection pool. there is no reason to kill idle connections since they are idle. they do not cause any issue except they might exhaust the amount of allowed connections. if it is a problem the execute “kill <thread_id>”. if not – forget about them

Mohammad1_313 2021-08-26 00:13:45
svart 2021-08-26 00:01:25
you’d better ask them

ask who?
this screenshot of the code is from a question on StackOverflow on another topic and I can not ask there this question
I just tried to use it as an example to explain my question
btw I find my answer somewhere else
thank u for your reply

N K 2021-08-26 00:28:32
Mysql db is stuck, can see there is lock in db and incremental backup is also stuck
N K 2021-08-26 00:28:51
What can be possible reason, cant execute simple select query as well
N K 2021-08-26 00:29:15
Can be backup reason for lock or the lock is the reason of db slowness and stuck backup
N K 2021-08-26 00:29:19
Pls suggest
yolo_xxi 2021-08-26 03:27:04
svart 2021-08-26 00:03:15
looks like you have idle connections or connection pool. there is no reason to kill idle connections since they are idle. they do not cause any issue except they might exhaust the amount of allowed connections. if it is a problem the execute “kill <thread_id>”. if not – forget about them

Alright. Thank you

MasterZiv 2021-08-26 07:36:55
N K 2021-08-26 00:28:51
What can be possible reason, cant execute simple select query as well

Look into the logs

MasterZiv 2021-08-26 07:37:53
N K 2021-08-26 00:29:19
Pls suggest

To little information to judge, you have to study more

mohammadEn1996 2021-08-27 21:33:42
Hello guys
I wanted to insert some varchar data in python to mysql with mysql.connector library
some of characters don’t be utf-8 and mysql will show them ? instead of

I tried different types of
utf8-general-ci and utf8mb4-general-ci but it didn’t work

anyone can help I really appreciate 🙏🙏

mohammadEn1996 2021-08-27 23:10:29
mohammadEn1996 2021-08-27 21:33:42
Hello guys
I wanted to insert some varchar data in python to mysql with mysql.connector library
some of characters don’t be utf-8 and mysql will show them ? instead of

I tried different types of
utf8-general-ci and utf8mb4-general-ci but it didn’t work

anyone can help I really appreciate 🙏🙏

It seems my problem solved by itself 🤔
I exactly don’t know what I did
But consider you should set your collation to utf8mb4
If it didn’t work use encode and so send it to mysql

Good luck 👍

MasterZiv 2021-08-27 23:29:26
mohammadEn1996 2021-08-27 21:33:42
Hello guys
I wanted to insert some varchar data in python to mysql with mysql.connector library
some of characters don’t be utf-8 and mysql will show them ? instead of

I tried different types of
utf8-general-ci and utf8mb4-general-ci but it didn’t work

anyone can help I really appreciate 🙏🙏

This is a very complex question actually, this can be by many different reasons.
So there is no use in asking, you just have to sit back and check all the stuff one by one

thanosphan 2021-08-28 09:28:58
Mohammad1_313 2021-08-25 21:07:31
Hi
i have a question about below example
i wanna know is there any reason why in below example they create seperate table for Category
why dont they add a Category column to question table instead?

They might have thought about normalisation in case they want to expand the category table with more columns

thanosphan 2021-08-28 09:31:00
yolo_xxi 2021-08-25 16:32:58
Hi guys, need some help here,.my system kinda slow to connection to database. how to eliminate some of the sleep connection? is this the cause of the slow loading at the system?

Slow to connect and having idle connections are unrelated. Idle connections are probably coming your pools, as someone pointed out already. You need to explain what slowness you see and when exactly

Deb_575 2021-08-28 15:32:17
What process do you implement for bulk update. I have one table of size 926gb and I need to update one column to null where all records are less than Jan 2021. I tried the obvious way but it’s taking forever. Any suggestion?
piterden 2021-08-28 15:37:02
Deb_575 2021-08-28 15:32:17
What process do you implement for bulk update. I have one table of size 926gb and I need to update one column to null where all records are less than Jan 2021. I tried the obvious way but it’s taking forever. Any suggestion?

How many rows are in your table?

Deb_575 2021-08-28 15:43:17
10 million
piterden 2021-08-28 15:45:12
How much time the select of 5000 rows takes?
svart 2021-08-28 17:32:24
Deb_575 2021-08-28 15:32:17
What process do you implement for bulk update. I have one table of size 926gb and I need to update one column to null where all records are less than Jan 2021. I tried the obvious way but it’s taking forever. Any suggestion?

Percona tools has something for batch updates if you want but it is not a big deal to write something simple on your own. Honestly saying, 10m rows is almost nothing

piterden 2021-08-28 18:08:25
Deb_575 2021-08-28 15:43:17
10 million

1. Optimize your queries.
2. Normalize your data.
3. Make 1 for 2.

piterden 2021-08-28 18:09:36
I just do the same for 20KK 55Gb size
piterden 2021-08-28 18:09:49
Smoke indexes
piterden 2021-08-28 18:09:52
Deeper
ceo_lupeko 2021-08-28 18:18:29
Will a table written on MySQL 5.7 be work on MySQL 8??
piterden 2021-08-28 18:21:05
ceo_lupeko 2021-08-28 18:18:29
Will a table written on MySQL 5.7 be work on MySQL 8??

There is an update guide on the official site

ceo_lupeko 2021-08-28 18:24:32
Yeah, but I wanna know: I made a table on my old device with MySQL 5.7 and can I work with this table but already on new device with MySQL 8?
thanosphan 2021-08-28 19:06:42
What device are you referring to?
MasterZiv 2021-08-29 08:43:05
Deb_575 2021-08-28 15:32:17
What process do you implement for bulk update. I have one table of size 926gb and I need to update one column to null where all records are less than Jan 2021. I tried the obvious way but it’s taking forever. Any suggestion?

Write a cursor to select the rows you need to update.
Ensure the query filter is covered by an effective index, if not, you have to create one.

Run the cursor and in the body of it update the current row with the desired values. Keep counter of processed rows and commit the current transaction every N rows, where N is something like 100 or 1000,or maybe more.
Also ensue all your process can be killed and restarted at any time.
Add indication of overall process status by selecting periodically the number of rows processed so far.

All this code is practical to organize in the form of stored procedure.

MasterZiv 2021-08-29 08:44:01
ceo_lupeko 2021-08-28 18:18:29
Will a table written on MySQL 5.7 be work on MySQL 8??

It will it will

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