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What is InnoDB and MyISAM in MySQL?
... INSERT statement can be executed to add rows to the end of the table with select at same time if there are no holes/deleted rows in middle of table (at time of concurrent insert).
The default isolation level og mysql InnoDB is "Read Repeatable". For MyISAM, there is no transaction. InnoDB uses row...
How to change position of Toast in Android?
...ited Sep 12 '17 at 10:27
Gorgon_Union
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answered Jul 25 '17 at 16:56
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What is the difference between sql and mysql [closed]
...onal Database Management Systems allow the user to add, remove, update, or select records. Things like MySQ are the actual Management Systems which allow you to store and retrieve your data, whereas SQL is the actual language to do so.
The basic SQL is somewhat universal - Selects usually look the ...
How to split the name string in mysql?
...ast names. The middle name will show as NULL if there is no middle name.
SELECT
SUBSTRING_INDEX(SUBSTRING_INDEX(fullname, ' ', 1), ' ', -1) AS first_name,
If( length(fullname) - length(replace(fullname, ' ', ''))>1,
SUBSTRING_INDEX(SUBSTRING_INDEX(fullname, ' ', 2), ' ', -1) ,NU...
INSERT INTO…SELECT for all MySQL columns
... manual. Try this:
INSERT INTO this_table_archive (col1, col2, ..., coln)
SELECT col1, col2, ..., coln
FROM this_table
WHERE entry_date < '2011-01-01 00:00:00';
If the id columns is an auto-increment column and you already have some data in both tables then in some cases you may want to omit t...
MySQL Query to select data from last week?
Hi I have a table with a date field and some other information.
I want to select all entries from the past week, (week start from Sunday).
...
How to convert an entire MySQL database characterset and collation to UTF-8?
...
You can create the sql to update all tables with:
SELECT CONCAT("ALTER TABLE ",TABLE_SCHEMA,".",TABLE_NAME," CHARACTER SET utf8 COLLATE utf8_general_ci; ",
"ALTER TABLE ",TABLE_SCHEMA,".",TABLE_NAME," CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci; ")
AS a...
MySQL JOIN the most recent row only?
...
You may want to try the following:
SELECT CONCAT(title, ' ', forename, ' ', surname) AS name
FROM customer c
JOIN (
SELECT MAX(id) max_id, customer_id
FROM customer_data
GROUP BY customer_id
...
How to avoid mysql 'Deadlock found when trying to get lock; try restarting transaction'
...now() - INTERVAL 900 SECOND
To
DELETE FROM onlineusers
WHERE id IN (
SELECT id FROM onlineusers
WHERE datetime <= now() - INTERVAL 900 SECOND
ORDER BY id
) u;
Another thing to keep in mind is that mysql documentation suggest that in case of a deadlock the client should retry autom...
MySQL Results as comma separated list
...
You can use GROUP_CONCAT to perform that, e.g. something like
SELECT p.id, p.name, GROUP_CONCAT(s.name) AS site_list
FROM sites s
INNER JOIN publications p ON(s.id = p.site_id)
GROUP BY p.id, p.name;
share
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