Sql mutations: Difference between revisions
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Changing data in your database.<br> | |||
See [[sql schemas]] for instructions on how to change your database structure. | |||
= INSERT = | = INSERT = | ||
<blockquote> | <blockquote> | ||
Add rows to a table. | Add rows to a table. | ||
Insert | Insert multiple rows. | ||
<syntaxhighlight lang="MySQL"> | <syntaxhighlight lang="MySQL"> | ||
# table ( columns ) | # table ( columns ) | ||
Line 13: | Line 16: | ||
</syntaxhighlight> | </syntaxhighlight> | ||
Insert | Insert row if match does not exist. | ||
<syntaxhighlight lang="MySQL"> | <syntaxhighlight lang="MySQL"> | ||
# Add 'Rupert' to users if does not exist | # Add 'Rupert' to users if does not exist | ||
Line 20: | Line 23: | ||
WHERE NOT EXISTS (SELECT name FROM users WHERE name = 'Rupert') LIMIT 1; | WHERE NOT EXISTS (SELECT name FROM users WHERE name = 'Rupert') LIMIT 1; | ||
</syntaxhighlight> | </syntaxhighlight> | ||
</blockquote><!-- Insertion --> | |||
= UPDATE = | |||
<blockquote> | |||
Update an existing row. | |||
<syntaxhighlight lang="MySQL"> | <syntaxhighlight lang="MySQL"> | ||
UPDATE users | UPDATE users | ||
Line 27: | Line 34: | ||
WHERE id = 190; | WHERE id = 190; | ||
</syntaxhighlight> | </syntaxhighlight> | ||
= | </blockquote><!-- UPDATe --> | ||
= DELETE = | |||
<blockquote> | <blockquote> | ||
Delete an existing row. | |||
<syntaxhighlight lang="MySQL"> | <syntaxhighlight lang="MySQL"> | ||
DELETE FROM | DELETE FROM users | ||
WHERE | WHERE id = 100; | ||
</syntaxhighlight> | </syntaxhighlight> | ||
</blockquote><!-- | </blockquote><!-- DELETE --> |
Latest revision as of 18:37, 19 September 2021
Changing data in your database.
See sql schemas for instructions on how to change your database structure.
INSERT
Add rows to a table.
Insert multiple rows.
# table ( columns ) # | | INSERT INTO tasks(subject, start_date, end_date, description) VALUES ('Task 1','2010-01-01','2010-01-02','Description 1'), ('Task 2','2010-01-01','2010-01-02','Description 2'), ('Task 3','2010-01-01','2010-01-02','Description 3');Insert row if match does not exist.
# Add 'Rupert' to users if does not exist INSERT INTO users (name, address, tele) SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp WHERE NOT EXISTS (SELECT name FROM users WHERE name = 'Rupert') LIMIT 1;
UPDATE
Update an existing row.
UPDATE users set email = "user@domain.com" WHERE id = 190;
DELETE
Delete an existing row.
DELETE FROM users WHERE id = 100;