I have found this tutorial, which says that question can be solved this way: Multiple-field constraint: For my simplified database: I wrote such sql code, which has an idea to connect 2 columns from 2 tables. In addition, I would like to add unique constraint on 2 field of S2T table: But I get an error, sayin…
Tag: alter-table
Altering column size in SQL Server
How to change the column size of the salary column in the employee table from numeric(18,0) to numeric(22,5) Answer
How to alter a column’s data type in a PostgreSQL table?
Entering the following command into a PostgreSQL interactive terminal results in an error: What is the correct command to alter the data type of a column? Answer See documentation here: http://www.postgresql.org/docs/current/interactive/sql-altertable.html
Change a Nullable column to NOT NULL with Default Value
I came across an old table today with a datetime column called ‘Created’ which allows nulls. Now, I’d want to change this so that it is NOT NULL, and also include a constraint to add in a default …
Unable to drop constraint in SQL server 2005, “Could not drop constraint. See previous errors”
I’m trying to drop a constraint on a DB table, something like: But the execution just runs and runs. If I stop it I see: Web search throws up various pages but note that the constraint is properly named and I am trying to remove it using the correct name Answer Found a way to sort this, although I don&#…