What does rows mean in MySQL explain?
rows (JSON name: rows ) The rows column indicates the number of rows MySQL believes it must examine to execute the query. For InnoDB tables, this number is an estimate, and may not always be exact.
What is the maximum number of rows?
1,048,576 rows
Worksheet and workbook specifications and limits
| Feature | Maximum limit |
|---|---|
| Total number of rows and columns on a worksheet | 1,048,576 rows by 16,384 columns |
| Column width | 255 characters |
| Row height | 409 points |
| Page breaks | 1,026 horizontal and vertical |
How many rows can a table hold MySQL?
A MySQL row-size limit of 65,535 (regardless of the storage engine). So, for InnoDB, you can have 1,073,741,824 rows. But, more rows can be added if the row size is smaller.
Which is the best way to count rows in MySQL?
When you COUNT (*) it takes in count column indexes, so it will be the best result. Mysql with MyISAM engine actually stores row count, it doensn’t count all rows each time you try to count all rows. (based on primary key’s column) Using PHP to count rows is not very smart, because you have to send data from mysql to php.
Is it smart to use PHP to count rows?
Using PHP to count rows is not very smart, because you have to send data from mysql to php. Why do it when you can achieve the same on the mysql side?
Why does MySQL Select Count ( * ) take so long?
Doing a select count (*) reads EVERY data block. Here’s a cheap way to get an estimated row count: Even if you did select count (id), it might still take a very long time, unless you have a secondary index on id (also assuming id is a PRIMARY KEY).
How to count number of rows in SQL?
When you select data rows, just append the SQL_CALC_FOUND_ROWS keyword after SELECT: After you have selected needed rows, you can get the count with this single query: FOUND_ROWS () has to be called immediately after the data selecting query.