What is intersect in sql

what is intersect in sql The SQL INTERSECT clause/operator is used to combine two SELECT statements, but returns rows only from the first SELECT statement that are identical to a row in the second SELECT statement. This means INTERSECT returns only common rows returned by the two SELECT statements.

What is intersect in sql Read More

What is denormalization in sql

what is denormalization in sql Denormalization is a strategy used on a previously-normalized database to increase performance. In computing, denormalization is the process of trying to improve the read performance of a database, at the expense of losing some write performance, by adding redundant copies of data or by grouping data.

What is denormalization in sql Read More

Tsql array parameter

tsql array parameter SELECT ProductId, Name, Tags FROM Product WHERE ‘clothing’ IN (SELECT value FROM STRING_SPLIT(Tags, ‘,’)); pass array parameter to stored procedure c# CREATE TYPE dbo.IDList AS TABLE ( ID INT ); GO CREATE PROCEDURE dbo.DoSomethingWithEmployees @List AS dbo.IDList READONLY AS BEGIN SET NOCOUNT ON; SELECT ID FROM @List; END GO pass array parameter […]

Tsql array parameter Read More

Sql update

sql update UPDATE table_name SET column1 = value1, column2 = value2, … WHERE condition; SQL Update Mit UPATE werden Datenwerte in der Datenbank aktualisiert. Nach Bedürfnis können auch mehrere Datensätze auf einmal verändert werden. Mit WHERE werden nur bestimmte Datensätze zu aktualisiert. UPDATE suppliers SET supplier_id = 50, supplier_name = ‘Apple’, city = ‘Cupertino’ WHERE […]

Sql update Read More

Sql server add column

sql add column ALTER TABLE Customers ADD Email varchar(255); sqlserver add column to table ALTER TABLE dbo.doc_exa ADD column_b VARCHAR(20) NULL, column_c INT NULL ; create column sql server ALTER TABLE table_name ADD column_name datatype; sql server add column ALTER TABLE dbo.doc_exa ADD column_b VARCHAR(20) NULL, column_c INT NULL ; alter table add column ALTER […]

Sql server add column Read More