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I tried the SQL code:
explain SELECT * FROM myTable LIMIT 1
As a result I got:
id select_type table type possible_keys key key_len ref **rows**
1 SIMPLE myTable ALL NULL NULL NULL NULL **32117**
Do you know why the query would run though all rows instead of simply picking the first row? What can I change within the query (or in my table) to reduce the line amount for a similar result?
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If you don't need to omit any rows, you can use SQL Server's TOP clause to limit the rows returned. It is placed immediately after SELECT. The TOP keyword is followed by integer indicating the number of rows to return. In our example, we ordered by price and then limited the returned rows to 3.
LIMIT clause in the SQL is used to restrict the number of records. In simple words, it is used to set an upper limit on the number of tuples returned for any given query.
The LIMIT clause is used to set an upper limit on the number of tuples returned by SQL. It is important to note that this clause is not supported by all SQL versions. The LIMIT clause can also be specified using the SQL 2008 OFFSET/FETCH FIRST clauses.
In the SELECT argument, the LIMIT clause is used to LIMIT the number of rows to be returned.
The rows count shown is only an estimate of the number of rows to examine. It is not always equal to the actual number of rows examined when you run the query.
In particular:
LIMIT is not taken into account while estimating number of rows Even if you have LIMIT which restricts how many rows will be examined MySQL will still print full number.
Source
When the query actually runs only one row will be examined.
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