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Questions - unique-constraint

Partial unique index in Postgres to ensure existence of a row that satisfies the constraint?

I have a users table, a teams table and a users_teams table. I am looking for a way in postgres to do the following: I want to ensure that a user always has a default team, a record with is_default tr...
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bencex

postgresql

constraints

unique-constraint

unique-index

Votes: 0

Answers: 1

Latest Answer

Add a foreign key that is NOT NULL to the users table that points to the default team of the user.
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Laurenz Albe

SQL Unique Constraint on Subset of data in table

I have a SQL Server table tbl_Submissions which contains a number of records for any given CaseID. Each Submission has an AuthorisedStatus field which can be "Authorised", "Rejected&quo...
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BiigJiim

sql-server

unique-constraint

unique-key

Votes: 0

Answers: 1

Latest Answer

It could be implemeneted using filtered index: CREATE UNIQUE INDEX udx ON tbl_Sumbissions(CaseID) WHERE AuthorisedStatus = 'Authorised'
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Lukasz Szozda

MySQL how to update multiple rows without breaking unique constraint or using placeholder row

In MySQL, I have a table named Channel (Auto-generated by Prisma ORM) CREATE TABLE `Channel` ( `id` INTEGER UNSIGNED NOT NULL AUTO_INCREMENT, `guildId` INTEGER UNSIGNED NOT NULL, `name` VA...
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Average Capitalist

mysql

sql

sql-update

uniqueidentifier

unique-constraint

Votes: 0

Answers: 0

insert row if one with equal value does not already exist

I'm trying to do an insert into table if the table doesn't already contain a field with a specified value. For this I am using this command: INSERT INTO zyprexa (NULL,'hello',0,0,0) SELECT date WHERE ...
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guillanBesada

sqlite

sql-insert

exists

unique-constraint

Votes: 0

Answers: 1

Latest Answer

The correct syntax is: INSERT INTO zyprexa (col1, col2, col3, col4, col5) SELECT NULL, 'hello', 0, 0, 0 WHERE NOT EXISTS (SELECT 1 FROM zyprexa WHERE date = 'hello'); where col1, col2, col3, col4, ...
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forpas

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