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Is it a good idea to index datetime field in mysql?
...ne table with 4 million records. Most of my queries use datetime clause to select data. Is it a good idea to index datetime fields in mysql database?
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How do write IF ELSE statement in a MySQL query
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You probably want to use a CASE expression.
They look like this:
SELECT col1, col2, (case when (action = 2 and state = 0)
THEN
1
ELSE
0
END)
as state from tbl1;
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How to recover MySQL database from .myd, .myi, .frm files
...ql\data\foldername\.mydfiles
Then visit localhost/phpmyadmin in a browser. Select the database you have just pasted into the mysql\data folder, and click on Export in the navigation bar. Chooses the export it as a .sql file. It will then pop up asking where the save the file
And that is it! You (s...
How to drop unique in MySQL?
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DROP INDEX column_name ON table_name
Select the database and query form the sql tab.This removes the index of the particular column. It worked for me in PHP MyADMIN
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Error in exception handler. - Laravel
...It printed could not find driver. And then I found out I had installed php-mysql, while php7.0-mysql was required. This link also helped me - digitalocean.com/community/tutorials/…
– Udayraj Deshmukh
Jun 18 '17 at 7:21
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How do I list all the columns in a table?
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For Oracle (PL/SQL)
SELECT column_name
FROM user_tab_cols
WHERE table_name = 'myTableName'
For MySQL
SHOW COLUMNS FROM table_name
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mysql :: insert into table, data from another table?
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INSERT INTO action_2_members (campaign_id, mobile, vote, vote_date)
SELECT campaign_id, from_number, received_msg, date_received
FROM `received_txts`
WHERE `campaign_id` = '8'
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Joining three tables using MySQL
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Simply use:
select s.name "Student", c.name "Course"
from student s, bridge b, course c
where b.sid = s.sid and b.cid = c.cid
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How to check if field is null or empty in MySQL?
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Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
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mysql_config not found when installing mysqldb python interface
...one Building dependency tree Reading state information...Done Note, selecting libmysqlclient15-dev instead of libmysqlclient-dev Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required...