MySQL | Tutes Club

How to change WordPress user roles in MySQL database using PhpMyAdmin?

We will be editing the database rows using PhpMyAdmin tool given with cPanel by many hosting companies

You can change the WordPress user roles by following the given steps:

Step 1: Open phpMyAdmin on cPanel.

Step 2: Open the wp_usermeta or xxx_usermeta table in the database as highlighted. (wp_ is just prefix, your table prefix may be different)

Step 3: In wp_usermeta table, you can find wp_capabilities under meta_key column.

Step 4: The roles are saved in form of serialized PHP array. Change the user role you want to assign to the current user by changing the meta_value as:

Subscriber
a:1:{s:10:"subscriber";b:1;}

Contributor
a:1:{s:11:"contributor";b:1;}

Author
a:1:{s:6:"author";b:1;}

Editor
a:1:{s:6:"editor";b:1;}

Administrator
a:1:{s:13:"administrator";b:1;}

MySQL error 1449: The user specified as a definer does not exist

Why this error happens?

Most of the times, reason is that your database dump through command line or PhpMyAdmin or even other libraries can have SQL’s Definer statements. Now, as per MySQL’s Official Documentation:

The DEFINER clause specifies the MySQL account to be used when checking access privileges at routine execution time for routines that have the SQL SECURITY DEFINER characteristic.
MySQL Reference Manual v8.0

Solution: MySQL mysqldump create a safe backup to ensure no corruption

Use the following command to create backup of your mysql database. Put the command in terminal

mysqldump -hHOST -uUSERNAME -p DATABASE_NAME | sed -e 's/DEFINER[ ]*=[ ]*[^*]*\*/\*/' > BACKUP_NAME.sql

With gzip compression > backup

mysqldump -hHOST -uUSERNAME -p DATABASE_NAME | sed -e 's/DEFINER[ ]*=[ ]*[^*]*\*/\*/' | gzip > BACKUP_NAME.sql

Reference: https://stackoverflow.com/a/9447215/2229148

Magento 2 – How to manage multi domain website store setup URLs

select * from `core_config_data` where path like 'web/%'

How to tweak Magento 2 for two letter search in fulltext mode

The problem:

Magento 2 wont return any search results if the search token is 2 letters in length.

Solution:

Alter MySQL conf file. Edit my.cnf file on your server
In CentOS, use command

nano /etc/my.cnf

and add the following lines:

ft_min_word_len=2
innodb_ft_min_token_size=2

Save using CTRL+x and then restart mysqld service.
Now we need to regenerate the index in order to get updated search results. Use the following SQL commands to regenerate:

Don’t forget to replace “jack_db1” with your database name

ALTER TABLE `jack_db1`.`catalogsearch_fulltext_scope1` DROP PRIMARY KEY, ADD PRIMARY KEY (`entity_id`, `attribute_id`) USING BTREE;
ALTER TABLE `jack_db1`.`catalogsearch_fulltext_scope1` DROP INDEX `FTI_FULLTEXT_DATA_INDEX`, ADD FULLTEXT `FTI_FULLTEXT_DATA_INDEX` (`data_index`);
ALTER TABLE `jack_db1`.`catalog_eav_attribute` DROP PRIMARY KEY, ADD PRIMARY KEY (`attribute_id`) USING BTREE;
ALTER TABLE `jack_db1`.`catalog_eav_attribute` DROP INDEX `CATALOG_EAV_ATTRIBUTE_USED_IN_PRODUCT_LISTING`, ADD INDEX `CATALOG_EAV_ATTRIBUTE_USED_IN_PRODUCT_LISTING` (`used_in_product_listing`) USING BTREE;
ALTER TABLE `jack_db1`.`catalog_eav_attribute` DROP INDEX `CATALOG_EAV_ATTRIBUTE_USED_FOR_SORT_BY`, ADD INDEX `CATALOG_EAV_ATTRIBUTE_USED_FOR_SORT_BY` (`used_for_sort_by`) USING BTREE;

References:
https://magento.stackexchange.com/a/157478/32283
https://dev.mysql.com/doc/refman/5.7/en/fulltext-fine-tuning.html

Magento 2 : How to fix tablespace for table exists | base table or view already exists

Fixing General error: 1813 Tablespace for table xx Please DISCARD the tablespace before IMPORT and SQLSTATE[42S01]: Base table or view already exists

Recently I encountered this error while upgrading an extension on Magento 2.2.2
The error was

SQLSTATE[HY000]: General error: 1813 Tablespace for table '`jack_db1`.`jill_table`' exists. Please DISCARD the tablespace before IMPORT., query was: CREATE TABLE IF NOT EXISTS `jill_table`

When I tried to fix the above error, I received:

SQLSTATE[42S01]: Base table or view already exists: 1050 Table '`jack_db1`.`jill_table`' already exists, query was: CREATE TABLE IF NOT EXISTS `jill_table`

So here is how to fix it:

Important Note: Replace jack_db1 with your database Name and jill_table with your table Name

PART 1 – Fixing MySQL backend

First log in to server and check the mysql data folder (mine was /var/lib/mysql/jack_db1)
say your database name is jack_db1 and your table is jill_table
so issue

ls /var/lib/mysql/jack_db1

You will find .frm and .idb files
Note that these files are present as a couple (each frm file has a corresponding idb file)
But the table that is causing you issues will have one of them missing.
.frm was missing in my case, so copy any other frm file and name it as jill_table.frm (i copied wishlist.frm using following command )
cd /var/lib/mysql/jack_db1;cp wishlist.frm jill_table.frm
use the following command to fix ownership

chown -R mysql:mysql /var/lib/mysql/jack_db1/*

Part 2: Fixing Magento Backend

Login to phpMyAdmin if available or use MySQL CLI to perform the following actions.
In the table setup_module of your magento installation
Delete the row which is related to your corrupted extension

DELETE FROM `setup_module` WHERE module="Custom_Module"

you can also do the same from phpMyAdmin

Now delete the table which was causing the issue, (you would not be able to view the table in phpmMyAdmin)
Just run the following query in SQL

DROP TABLE IF EXISTS `jill_table`;

Part 3: Upgrade the Magento using php cli

run the following commands:

rm -rf var/cache/*
rm -rf generated/*
php bin/magento module:enable Custom_Module --clear-static-content
php bin/magento setup:upgrade
#  Hopefully this time you wont see any errors, proceed as usual if upgrade command worked.
#  run
php bin/magento setup:di:compile
#  and 
php bin/magento setup:static-content:deploy -f

Good Luck with Magento 🙂

How to find rows which exist in new table but not in old table – MySQL

SQL Query:
SELECT t1.stone FROM newatt t1 LEFT JOIN att t2 ON t2.stone = t1.stone WHERE t2.stone IS NULL

newatt = new table (contains updated extra rows)

att = old table

stone = column name on both tables

Insert Indian States in Magento Database

Connect to your server’s database using mysql cli or phpmyadmin and use the following query

INSERT INTO `directory_country_region` VALUES 
(NULL,"IN","AP","Andhra Pradesh"),
(NULL,"IN","AR","Arunachal Pradesh"),
(NULL,"IN","AS","Assam"),
(NULL,"IN","BR","Bihar"),
(NULL,"IN","CG","Chhattisgarh"),
(NULL,"IN","GA","Goa"),
(NULL,"IN","GJ","Gujarat"),
(NULL,"IN","HR","Haryana"),
(NULL,"IN","HP","Himachal Pradesh"),
(NULL,"IN","JK","Jammu and Kashmir"),
(NULL,"IN","JH","Jharkhand"),
(NULL,"IN","KA","Karnataka"),
(NULL,"IN","KL","Kerala"),
(NULL,"IN","MP","Madhya Pradesh"),
(NULL,"IN","MH","Maharashtra"),
(NULL,"IN","MN","Manipur"),
(NULL,"IN","ML","Meghalaya"),
(NULL,"IN","MZ","Mizoram"),
(NULL,"IN","NL","Nagaland"),
(NULL,"IN","OD","Odisha"),
(NULL,"IN","PB","Punjab"),
(NULL,"IN","RJ","Rajasthan"),
(NULL,"IN","SK","Sikkim"),
(NULL,"IN","TN","Tamil Nadu"),
(NULL,"IN","TL","Telangana"),
(NULL,"IN","TR","Tripura"),
(NULL,"IN","UK","Uttarakhand"),
(NULL,"IN","UP","Uttar Pradesh"),
(NULL,"IN","WB","West Bengal"),
(NULL,"IN","AN","Andaman and Nicobar Islands"),
(NULL,"IN","CH","Chandigarh"),
(NULL,"IN","DH","Dadra and Nagar Haveli"),
(NULL,"IN","DD","Daman and Diu"),
(NULL,"IN","DL","Delhi"),
(NULL,"IN","LD","Lakshadweep"),
(NULL,"IN","PY","Puducherry");

Inserting into SQL without specifying primary column

If Primary key is set to Auto-increment, there are chances that you would not want to provide its value in insert query.

Here is how to do it in MySQL:
INSERT INTO table_name VALUES (NULL, 'column b', 'col c');

Assumption^: The first column is the primary key set to AI
Similarly you can skip columns for other non-required data:
INSERT INTO table_name(col b,col c) VALUES ('column b', 'col c');