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CREATE UNIQUE INDEX. The CREATE UNIQUE INDEX command creates a unique index on a table (no duplicate values allowed) Indexes are used to retrieve data from the database very fast. The users cannot see the indexes, they are just used to speed up searches/queries.
- CREATE VIEW
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- CREATE VIEW
5 Μαΐ 2023 · This topic describes how to create a unique index on a table in SQL Server by using SQL Server Management Studio or Transact-SQL. A unique index guarantees that the index key contains no duplicate values and therefore every row in the table is in some way unique.
The basic syntax of the command to create a unique index is as follows. CREATE UNIQUE INDEXindex_nameONtable_name | view_name(column_list); In this syntax, UNIQUE – keyword which tells SQL Server to create the new index as a unique index. table_name|view_name –the name of the table or view on which the unique index is to be created.
To create a unique index, you use the CREATE UNIQUE INDEX statement as follows: CREATE UNIQUE INDEX index_name. ON table_name(column_list); Code language: SQL (Structured Query Language) (sql) In this syntax: First, specify the name of the unique index after the CREATE UNIQUE INDEX keywords.
The SQL Unique Index ensures that no two rows in the indexed columns of a table have the same values (no duplicate values allowed). A unique index can be created on one or more columns of a table using the CREATE UNIQUE INDEX statement in SQL.
2 Αυγ 2021 · CREATE UNIQUE INDEX index_name ON table_name(column1, column2...) The index_name can be anything you want, but you should always use a name that makes sense . The table_name is of course the table you want to add the Unique Index to.
To create a UNIQUE index, you use the CREATE UNIQUE INDEX statement as follows: CREATE UNIQUE INDEX index_name. ON table_name(index_column_1,index_column_2,...); Code language: SQL (Structured Query Language) (sql) Another way to enforce the uniqueness of value in one or more columns is to use the UNIQUE constraint.
