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MS SQL Server - add index to existing table
0 points
TODO: indexy na koniec
In this article, we would like to show you how to add index to an existing table in MS SQL Server.
Quick solution:
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CREATE INDEX [index_name]2
ON [table_name] ([column1], [column2], [columnN]);or
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ALTER TABLE [table_name] 2
ADD INDEX [index_name] ([column2], [column2], [columnN]);To show how to add index to existing table, we will use the following table:
Note:
At the end of this article you can find database preparation SQL queries.
In this example, we will create an index for the salary column in users table.
Query:
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CREATE INDEX [salary_index]2
ON [users] ([salary]);Result:
1. Using query
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SHOW INDEX FROM [users] FROM [dirask]; -- where users-table_name, dirask-database_name
2. Using HeidiSQL
In this example, we will create an index on the name and surname columns in users table.
Query:
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CREATE INDEX [full_name_index]2
ON [users] ([name], [surname]);Result:
1. Using query
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SHOW INDEX FROM [users] FROM [dirask]; -- where users-table_name, dirask-database_name
2. Using HeidiSQL
In this example, we will create an index on two columns using ALTER TABLE statement.
Query:
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ALTER TABLE [users] 2
ADD INDEX [index_full_name] ([name], [surname]);Result:
1. Using query
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SHOW INDEX FROM [users] FROM [dirask]; -- where users-table_name, dirask-database_name
2. Using HeidiSQL
create_tables.sql file:
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CREATE TABLE [users] (2
[id] INT IDENTITY(1,1),3
[name] VARCHAR(50) NOT NULL,4
[surname] VARCHAR(50) NOT NULL,5
[salary] DECIMAL(15,2) NOT NULL,6
PRIMARY KEY ([id])7
);insert_data.sql file:
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INSERT INTO [users]2
( [name], [surname], [salary])3
VALUES4
('John', 'Stewart', '3512.00'),5
('Chris', 'Brown', '1344.00'),6
('Kate', 'Lewis', '6574.00'),7
('Ailisa', 'Gomez', '6500.00'),8
('Gwendolyn', 'James', '4200.00'),9
('Simon', 'Collins', '3320.00'),10
('Taylor', 'Martin', '1500.00'),11
('Andrew', 'Thompson', '2100.00');