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Excerpts from this Manual SHOW TABLE STATUS Syntax

    [{FROM | IN} db_name]
    [LIKE 'pattern' | WHERE expr]

SHOW TABLE STATUS works likes SHOW TABLES, but provides a lot of information about each non-TEMPORARY table. You can also get this list using the mysqlshow --status db_name command. The LIKE clause, if present, indicates which table names to match. The WHERE clause can be given to select rows using more general conditions, as discussed in Section 21.33, “Extensions to SHOW Statements”.

This statement also displays information about views.

SHOW TABLE STATUS output has the following columns:

  • Name

    The name of the table.

  • Engine

    The storage engine for the table. See Chapter 15, Alternative Storage Engines.

  • Version

    The version number of the table's .frm file.

  • Row_format

    The row-storage format (Fixed, Dynamic, Compressed, Redundant, Compact). For MyISAM tables, (Dynamic corresponds to what myisamchk -dvv reports as Packed. The format of InnoDB tables is reported as Redundant or Compact. For the Barracuda file format of the InnoDB Plugin, the format may be Compressed or Dynamic.

  • Rows

    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.

    The Rows value is NULL for tables in the INFORMATION_SCHEMA database.

  • Avg_row_length

    The average row length.

    Refer to the notes at the end of this section for related information.

  • Data_length

    For MyISAM, Data_length is the length of the data file, in bytes.

    For InnoDB, Data_length is the approximate amount of memory allocated for the clustered index, in bytes. Specifically, it is the clustered index size, in pages, multiplied by the InnoDB page size.

    Refer to the notes at the end of this section for information regarding other storage engines.

  • Max_data_length

    For MyISAM, Max_data_length is maximum length of the data file. This is the total number of bytes of data that can be stored in the table, given the data pointer size used.

    Unused for InnoDB.

    Refer to the notes at the end of this section for information regarding other storage engines.

  • Index_length

    For MyISAM, Index_length is the length of the index file, in bytes.

    For InnoDB, Index_length is the approximate amount of memory allocated for non-clustered indexes, in bytes. Specifically, it is the sum of non-clustered index sizes, in pages, multiplied by the InnoDB page size.

    Refer to the notes at the end of this section for information regarding other storage engines.

  • Data_free

    The number of allocated but unused bytes.

    This information is also shown for InnoDB tables (previously, it was in the Comment value). InnoDB tables report the free space of the tablespace to which the table belongs. For a table located in the shared tablespace, this is the free space of the shared tablespace. If you are using multiple tablespaces and the table has its own tablespace, the free space is for only that table. Free space means the number of bytes in completely free extents minus a safety margin. Even if free space displays as 0, it may be possible to insert rows as long as new extents need not be allocated.

    For partitioned tables, this value is only an estimate and may not be absolutely correct. A more accurate method of obtaining this information in such cases is to query the INFORMATION_SCHEMA.PARTITIONS table, as shown in this example:

        WHERE TABLE_SCHEMA = 'mydb'
        AND   TABLE_NAME   = 'mytable';

    For more information, see Section 21.13, “The INFORMATION_SCHEMA PARTITIONS Table”.

  • Auto_increment

    The next AUTO_INCREMENT value.

  • Create_time

    When the table was created.

  • Update_time

    When the data file was last updated. For some storage engines, this value is NULL. For example, InnoDB stores multiple tables in its system tablespace and the data file timestamp does not apply. Even with file-per-table mode with each InnoDB table in a separate .ibd file, change buffering can delay the write to the data file, so the file modification time is different from the time of the last insert, update, or delete. For MyISAM, the data file timestamp is used; however, on Windows the timestamp is not updated by updates so the value is inaccurate.

  • Check_time

    When the table was last checked. Not all storage engines update this time, in which case the value is always NULL.

  • Collation

    The table's character set and collation.

  • Checksum

    The live checksum value (if any).

  • Create_options

    Extra options used with CREATE TABLE. The original options supplied when CREATE TABLE is called are retained and the options reported here may differ from the active table settings and options.

  • Comment

    The comment used when creating the table (or information as to why MySQL could not access the table information).


  • For MEMORY tables, the Data_length, Max_data_length, and Index_length values approximate the actual amount of allocated memory. The allocation algorithm reserves memory in large amounts to reduce the number of allocation operations.

  • For NDB tables, the output of this statement shows appropriate values for the Avg_row_length and Data_length columns, with the exception that BLOB columns are not taken into account

  • For views, all the fields displayed by SHOW TABLE STATUS are NULL except that Name indicates the view name and Comment says view.

User Comments
  Posted by H Y on March 23, 2004
If you need to get hold of only one of these columns, there are sometimes another way. E.g. if you don't need row format, type, name, average row length and all the other stuff, but only want to see the total number of rows in a table, use COUNT(*).
  Posted by Steven Szelei on June 28, 2004
I was looking for a way to show the relationship of tables based on unique key, key, index, and foreign key constraints. I found that I can get some of the data using the admin statement SHOW INDEX FROM <<TBL>>. However this will give only the index name and the Column_name in the table that I am requesting from. I then did a SHOW CREATE TABLE <<TBL>> and this dumps the DDL script used to create the table. I would have to parse this information but could get everything I needed. I then found that SHOW TABLE STATUS LIKE <<TBL>> gave me The REFER information mapped to the column name. Unfortunatlly it did so in the Comments field as a string so uh! more parsing. This is what I have been able to discover so far and am still looking for a clean way to gather key, index, and constraint information to dynamically build table relationships. Also I noticed that the constraint names set in the DDL have not been preserved and mysql has given the constraints their own names. Names given keys are preserved. you can see this by running the show create table <<TBL>> on any table you have set constraints on.
  Posted by Bahadir Malkoç on December 5, 2005
Here is an example of using this command with php and get results...


$result mysql_query("SHOW TABLE STATUS FROM test;");
$array mysql_fetch_array($result)) {
$total $array[Data_length]+$array[Index_length];
Table: '
.$array[Name].'<br />
Data Size: '
.$array[Data_length].'<br />
Index Size: '
.$array[Index_length].'<br />
Total Size: '
.$total.'<br />
Total Rows: '
.$array[Rows].'<br />
Average Size Per Row: '
.$array[Avg_row_length].'<br /><br />


  Posted by dan f on December 6, 2005
Here is a perl script to add up free space per engine. Whether you are out of space depends on how you have configured MySQL. The InnoDB engine might be limited space, or it might be allowed to grow. The MyISAM space is probably in the file system, which has as much left as it has.

This script is a hack. Feel free to improve and post.

For some reason, I can't get it to format nicely, either.

#!/opt/gnu/bin/perl -w

use strict;

use Getopt::Long;
my @options;

# Get output immediately. It won't hurt performance.
use FileHandle;
autoflush STDERR;
autoflush STDOUT;

my $pw;
push(@options, "password=s", \$pw);

my $host = "localhost";
push(@options, "host=s", \$host);

die "Couldn't parse options" if !GetOptions(@options);

die "Must give -password\n" if !defined($pw);

my $cmd = mysql_cmd("show databases");
open(CMD, $cmd) or die "Couldn't $cmd: $!\n";
my @databases;
my $header = <CMD>;
while ( <CMD> ) {
#print "$_\n";
push (@databases, $_);

#print "@databases";

my %colmap = ( 'Data_length' => 6,
'Index_length' => 8,
'Engine' => 1,
'Comment' => 17 );

my %size;
my %total_size;
my %engine_map;

my $inno_db_free;
foreach my $db (@databases) {
print STDERR ".";
$cmd = mysql_cmd("use $db; show table status");

open(CMD, $cmd) or die "Couldn't $cmd: $!\n";
my $header = <CMD>;
my $total_size = 0;
if (defined($header)) {
$header =~ s/[\r\n]$//g;
my @head = split("\t", $header);

foreach my $col (keys %colmap) {
die "$db: Expected '$col', found '" . $head[$colmap{$col}] . "'"
if $head[$colmap{$col}] ne $col;

while (<CMD>) {
my @data = split("\t");
my ($data_length, $index_length) = @data[6,8];
my ($engine, $comment) = @data[1,17];
$size{$db}{$engine} += $data_length + $index_length;
$total_size{$db} += $data_length + $index_length;

if ( $comment =~ /InnoDB free: (\d+) kB/ ) {
die "Found two different inno DB free sized.\n"
if defined($inno_db_free) && $inno_db_free != $1;
$inno_db_free = $1;
print STDERR "\n";

print "NOTE: All numbers are in megabytes (M).\n";
printf("Inno DB free: %.1f\n", $inno_db_free / 1024)
if defined($inno_db_free);

printf("%-30s ", "database");
foreach my $engine (sort keys(%engine_map)) {
printf "%7s ", $engine;
printf "%8s", "total";
print "\n";

foreach my $db (sort {$total_size{$b} <=> $total_size{$a}} keys %total_size) {
printf("%-30s ", $db);
foreach my $engine (sort keys(%engine_map)) {
my $size= $size{$db}{$engine};
$size = 0 if !defined($size);
printf("%7.1f ", $size / 1024 / 1024);
printf("%8.1f\n", $total_size{$db} / 1024 / 1024);

sub mysql_cmd {
my $mysql_cmd = shift;

return "mysql -uroot -h$host -p$pw -e '$mysql_cmd'|";

Example output:

% ./ -p ...
NOTE: All numbers are in megabytes (M).
Inno DB free: 10755.0
database HEAP InnoDB MyISAM total
tldan 0.0 339.1 720.3 1059.4
ml3test7 0.0 1010.8 0.0 1010.8
ml3test6 0.0 930.4 0.0 930.4
test 0.0 655.4 0.0 655.4
blarg4 0.0 39.5 0.0 39.5

  Posted by Marc Zizka on January 6, 2006
For InnoDB tables, the Comment field of SHOW TABLE STATUS is useful for extracting foreign key information for older versions of MySQL. For versions since 5.0.6, you can query INFORMATION_SCHEMA. (See

The way the foreign key info is stored in the Comment field can be a pain to parse. Here's a snippet of PHP code that shows how to do this.

//DB connection already established
$res mysql_query("SHOW TABLE STATUS LIKE 'MY_TABLE'");
$row mysql_fetch_assoc($res);
$commentArr preg_split('/; */'$row['Comment']);

$foreignKeyArr = array(); //<-- We want to fill this.

foreach($commentArr as $comment) {
//Only work on InnoDB foreign key info.
'/\(`(.*)`\) REFER `(.*)\/(.*)`\(`(.*)`\)/',
$matchArr)) {
$primaryKeyFieldArr preg_split('/` `/'matchArr[1]);
$foreignKeyDatabase $matchArr[2];
$foreignKeyTable $matchArr[3];
$foreignKeyFieldArr preg_split('/` `/'$matchArr[4]);

$i 0$i count($primaryKeyFieldArr); $i++) {
$foreignKeyArr$primaryKeyFieldArr[$i] ] = array(
'db' => $foreignKeyDatabase,
'table' => $foreignKeyTable,
'field' => $foreignKeyFieldArr[$i]);

Now $foreignKeyArr holds a list of fields from MY_TABLE
that have a foreign key constraint. If MY_FK is a foreign
key referencing YOUR_ID in YOUR_TABLE, you will get:

$foreignKeyArr['MY_FK']['db'] == 'THIS_DATABASE'
$foreignKeyArr['MY_FK']['table'] == 'YOUR_TABLE'
$foreignKeyArr['MY_FK']['field'] == 'YOUR_ID'

  Posted by Brian Robinson on August 25, 2006
If you are REALLY desperate to get FK relationships you can always use a bit of JAVA code.
I know you Perl guys will balk at this - but the JDBC METADATA can give you this information quite easily.
maybe there is something similar for Perl DBI?

  Posted by Eric Brunson on February 5, 2007
Or you can read the foreign key relationships out of the information_schema. Java's not magic, you know, all that info is in there to be used by anything that can read it. ;-)
  Posted by andrew taylor on May 19, 2007
A handy one liner to get the total table size...requires ruby

mysqlshow -u <user> --password=<password> --status <dbname> | ruby -e 'puts STDIN.readlines[4..-2].inject(0) {|s,e| s += e.split("|")[7].to_i}'
  Posted by Scott Ripley on May 24, 2007
I've amended the above PHP script to format the output for an HTML table.


print('<table cols="6"><th>Table</th><th>Data Size</th><th>Index Size</th><th>Total size</th><th>Total Rows</th><th>Avg. Size per Row</th>');
$result mysql_query("SHOW TABLE STATUS FROM test;");

$array mysql_fetch_array($result)) {
$total $array[Data_length]+$array[Index_length];

if ( 
$array[Data_length] > ) {

'<tr><td align="center">');

' ' $array[Name] . '<br /></td><td align="center">');

if ( 
$array[Data_length] < 1024 ) {
' '.$array[Data_length].'</td><td align="center">';
        } elseif ( (
$array[Data_length] > 1024) && ($array[Data_length] < 1048576 ) ) {
printf('%.0fK',($array[Data_length] / 1024) );    
'</td><td align="center">');
        } elseif ( 
$array[Data_length] >= 1048576 ) {
printf('%.2fMB',($array[Data_length] / 1048576) );
'</td><td align="center">');


if ( 
$array[Index_length] < 1024 ) {
' '.$array[Index_length].'<br /></td><td align="center">';
        } elseif ( (
$array[Index_length] > 1024) && ($array[Index_length] < 1048576 ) ) {
printf('%.0fK',($array[Index_length] / 1024) );    
'<br /></td><td align="center">');
        } elseif ( 
$array[Index_length] >= 1048576 ) {
printf('%.2fMB',($array[Index_length] / 1048576) );
'<br /></td><td align="center">');

if ( 
$total 1024 ) {
' '.$total.'<br /></td><td align="center">';
        } elseif ( (
$total 1024) && ($total 1048576 ) ) {
printf('%.0fK',($total 1024) );    
'<br /></td><td align="center">');
        } elseif ( 
$total >= 1048576 ) {
printf('%.2fMB',($total 1048576) );
'<br /></td><td align="center">');

.$array[Rows].'</td><td align="center">



  Posted by Vasil Dimov on December 11, 2007
Since MySQL 5.1.23 the InnoDB free space that was present in INFORMATION_SCHEMA.TABLES.TABLE_COMMENT and in "SHOW ..." is moved to INFORMATION_SCHEMA.TABLES.DATA_FREE. The value is in kilobytes. Programs that parse TABLE_COMMENT need to be adjusted. See
  Posted by Marcos Gil Fuertes on February 7, 2008
To Marc Zizka:

I tried your script BUT got a problem with "SHOW TABLE STATUS". It only returns the first foreign key (in MySql 5.0.27).

Instead of it, I'm using "SHOW CREATE TABLE" and this regular expression:

'/FOREIGN KEY \(`(.*)`\) REFERENCES `(.*)` \(`(.*)`\)/'

I'm assuming that all the references are located in the same database.
  Posted by Ivan Cachicatari on February 29, 2012
You can found a custom SHOW TABLE STATUS command based on INFORMATION_SCHEMA database at:
That stored procedure returns a result like this:

| Table Name | Engine | Rows | Size | Collation |
| actor | InnoDB | 200 | 0.03 Mb | utf8_general_ci |
| actor_info | [VIEW] | - | - | - |
| address | InnoDB | 589 | 0.09 Mb | utf8_general_ci |
| category | InnoDB | 16 | 0.02 Mb | utf8_general_ci |
| city | InnoDB | 427 | 0.06 Mb | utf8_general_ci |
| country | InnoDB | 109 | 0.02 Mb | utf8_general_ci |
| customer | InnoDB | 541 | 0.12 Mb | utf8_general_ci |

  Posted by NOT_FOUND NOT_FOUND on July 2, 2014
MySQL 5.6 finally speeds up SHOW TABLE STATUS in cases where it used to perform miserably. Example for one of our databases containing 112 InnoDB tables, some of which have millions of rows:

MySQL 5.5.30: 32 seconds
MySQL 5.6.16: 0.3 seconds
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