You could create a user-defined function for this: CREATE FUNCTION dbo.GetValue(@ncode INT, @recid INT) RETURNS INT AS SELECT @recid * nvalue FROM c_const WHERE code = @ncode and then use that to define your computed column: ALTER TABLE dbo.YourTable ADD NewColumnName AS dbo.GetValue(ncodeValue, recIdValue)
Something like this: ALTER TABLE dbo.MyTable DROP COLUMN OldComputedColumn ALTER TABLE dbo.MyTable ADD OldComputedColumn AS OtherColumn + 10 Source
You need to wrap the SELECT statement into a derived table in order to be able to access the column alias: select cost1, quantity_1, cost_2, quantity_2 total_1 + total_2 as total_3 from ( select cost_1, quantity_1, cost_2, quantity_2, (cost_1 * quantity_1) as total_1, (cost_2 * quantity_2) as total_2 from data ) t There won’t be … Read more
You can use ISNULL(….) SET @Concatenated = ISNULL(@Column1, ”) + ISNULL(@Column2, ”) If the value of the column/expression is indeed NULL, then the second value specified (here: empty string) will be used instead.
You can create computed columns in your database tables. In the EF model you just annotate the corresponding properties with the DatabaseGenerated attribute: [DatabaseGenerated(DatabaseGeneratedOption.Computed)] public double Summ { get; private set; } Or with fluent mapping: modelBuilder.Entity<Income>().Property(t => t.Summ) .HasDatabaseGeneratedOption(DatabaseGeneratedOption.Computed) As suggested by Matija Grcic and in a comment, it’s a good idea to make … Read more