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Questions - unique-key

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

ADD COLUMN with CONSTRAINT

I have a table name Stu_d. In this, I have created 3 columns {Stu_id INT PRIMARY KEY, Name VARCHAR(20), Roll_no INT(5)}. I need to add 1 more column with the name of Mobile_no with INT data type and h...
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Vasu Gupta

mysql

primary-key

rdbms

alter-table

unique-key

Votes: 0

Answers: 1

Latest Answer

The syntax for this is ALTER TABLE Stu_d ADD COLUMN Mobile_no INT(10) UNIQUE ; if you want to name the constraint then use ALTER TABLE Stu_d ADD COLUMN Mobile_no INT(10) ; ALTER TABLE Stu_d ADD CONST...
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user18098820

how to add unique key constraint on column in table in ERD tool in pgAdmin4

I am creating a schema diagram using the ERD tool and want to add a unique key constraint in my column but it seems there is only not null and primary key option is there any idea how to add it? how t...
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badrik patel

postgresql

pgadmin-4

unique-key

Votes: 0

Answers: 2

Latest Answer

You can do it in Constraints tab
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Philippe

Does using a modified UUID with repeating characters as Firestore Document ID create performance/hotspotting risk?

I'm working with Google Cloud Firestore. For a particular Document ID, I'm using a modified UUID. In this modified UUID, the last 4 characters are always a string from an integer between 0000-2000. Ex...
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timberlakegregg

google-cloud-firestore

uniqueidentifier

unique-key

Votes: 0

Answers: 1

Latest Answer

Any sort of limits in Firestore are only triggered as a result of specific activity, including both the data being added to an index, the nature of the data, and the rate at which that data is added. ...
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Doug Stevenson

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