A database index is a data structure that improves the speed of table operations. Indexes can be created using one or more columns, providing the basis for fast random lookups and efficient ordering of record access.
The best practice for using MySQL indexes is.
If the table is very large for a CSV, then using an index will insert records to the end.
An index creates a series of rows in a table.
Indexes can speed up certain selection operations
For tables with indexes, INSERT and UPDATE statements take more time, while for these tables, SELECT statements become faster. The reason is that when the database is inserting or updating, it also needs to insert or update the index value.
MySQL index example: If the CSV file is spread out, the index maintains the order of the rows.
Let's look at an example of creating an index.
Create tables and indexes on specific columns.
mysql> create table IndexingDemo -> ( -> Id int, -> Name varchar(100) -> ); Query OK, 0 rows affected (0.86 sec)
Syntax for creating an index on a table.
create index yourIndexName on yourTableName(column_name);
The following is the output.
mysql> create index indexName on IndexingDemo(Name); Query OK, 0 rows affected (0.75 sec) Records: 0 Duplicates: 0 Warnings: 0
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