Count table rows - mysql

Question

What is the MySQL command to retrieve the count of records in a table?

Answer 1

SELECT COUNT(*) FROM fooTable;
will count the number of rows in the table.
See the reference manual.

Answer 2

Because nobody mentioned it:
show table status;
lists all tables along with some additional information, including estimated rows for each table. This is what phpMyAdmin is using for its database page.
This information is available in MySQL 4, probably in MySQL 3.23 too - long time prior information schema database.
The number shown is estimated for InnoDB and TokuDB but it is absolutely correct for MyISAM and Aria (Maria) storage engines.
Per the documentation:
The number of rows. Some storage engines, such as MyISAM, store the
exact count. For other storage engines, such as InnoDB, this value is
an approximation, and may vary from the actual value by as much as 40%
to 50%. In such cases, use SELECT COUNT(*) to obtain an accurate
count.
This also is fastest way to see the row count on MySQL, because query like:
select count(*) from table;
Doing full table scan what could be very expensive operation that might take hours on large high load server. It also increase disk I/O.
The same operation might block the table for inserts and updates - this happen only on exotic storage engines.
InnoDB and TokuDB are OK with table lock, but need full table scan.

Answer 3

We have another way to find out the number of rows in a table without running a select query on that table.
Every MySQL instance has information_schema database. If you run the following query, it will give complete details about the table including the approximate number of rows in that table.
select * from information_schema.TABLES where table_name = 'table_name'\G

Answer 4

Simply:
SELECT COUNT(*) FROM `tablename`

Answer 5

select count(*) from YourTable

Answer 6

If you have several fields in your table and your table is huge, it's better DO NOT USE * because of it load all fields to memory and using the following will have better performance
SELECT COUNT(1) FROM fooTable;

Answer 7

Just do a
SELECT COUNT(*) FROM table;
You can specify conditions with a Where after that
SELECT COUNT(*) FROM table WHERE eye_color='brown';

Answer 8

As mentioned by Santosh, I think this query is suitably fast, while not querying all the table.
To return integer result of number of data records, for a specific tablename in a particular database:
select TABLE_ROWS from information_schema.TABLES where TABLE_SCHEMA = 'database'
AND table_name='tablename';

Answer 9

If you have a primary key or a unique key/index, the faster method possible (Tested with 4 millions row tables)
SHOW INDEXES FROM "database.tablename" WHERE Key_Name=\"PRIMARY\"
and then get cardinality field (it is close to instant)
Times where from 0.4s to 0.0001ms

Answer 10

$sql="SELECT count(*) as toplam FROM wp_postmeta WHERE meta_key='ICERIK' AND post_id=".$id;
$total = 0;
$sqls = mysql_query($sql,$conn);
if ( $sqls ) {
$total = mysql_result($sqls, 0);
};
echo "Total:".$total;`

Answer 11

You have to use count() returns the number of rows that matches a
specified criteria
select count(*) from table_name;

Answer 12

It can be convenient to select count with filter by indexed field. Try this
EXPLAIN SELECT * FROM table_name WHERE key < anything;