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Adding options --idxstat and selectivity index request

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root 2015-07-02 12:16:02 +02:00
parent 044f7c52c6
commit 43fd15f00d
1 changed files with 47 additions and 0 deletions
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47
mysqltuner.pl
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@ -1420,6 +1420,53 @@ sub mysql_indexes {
infoprint "Skip Index metrics from information schema missing in this version\n";
return;
}
my $selIdxReq= <<'ENDSQL';
SELECT
CONCAT(CONCAT(t.TABLE_SCHEMA, '.'),t.TABLE_NAME) AS 'table'
, CONCAT(CONCAT(CONCAT(s.INDEX_NAME, '('),s.COLUMN_NAME), ')') AS 'index'
, s.SEQ_IN_INDEX AS 'seq'
, s2.max_columns AS 'maxcol'
, s.CARDINALITY AS 'card'
, t.TABLE_ROWS AS 'est_rows'
, ROUND(((s.CARDINALITY / IFNULL(t.TABLE_ROWS, 0.01)) * 100), 2) AS 'sel'
FROM INFORMATION_SCHEMA.STATISTICS s
INNER JOIN INFORMATION_SCHEMA.TABLES t
ON s.TABLE_SCHEMA = t.TABLE_SCHEMA
AND s.TABLE_NAME = t.TABLE_NAME
INNER JOIN (
SELECT
TABLE_SCHEMA
, TABLE_NAME
, INDEX_NAME
, MAX(SEQ_IN_INDEX) AS max_columns
FROM INFORMATION_SCHEMA.STATISTICS
WHERE TABLE_SCHEMA NOT IN ('mysql', 'information_schema', 'performance_schema')
GROUP BY TABLE_SCHEMA, TABLE_NAME, INDEX_NAME
) AS s2
ON s.TABLE_SCHEMA = s2.TABLE_SCHEMA
AND s.TABLE_NAME = s2.TABLE_NAME
AND s.INDEX_NAME = s2.INDEX_NAME
WHERE t.TABLE_SCHEMA NOT IN ('mysql', 'information_schema', 'performance_schema')
AND t.TABLE_ROWS > 10
AND s.CARDINALITY IS NOT NULL
AND (s.CARDINALITY / IFNULL(t.TABLE_ROWS, 0.01)) < 8.00
ORDER BY sel
LIMIT 10;
ENDSQL
my @idxinfo=select_array($selIdxReq);
infoprint "Worst selectivity indexes:\n";
foreach (@idxinfo) {
debugprint "$_\n";
my @info= split /\s/;
infoprint "Index: ".$info[1]."\n";
infoprint " +-- COLONNE : ".$info[0]."\n";
infoprint " +-- NB SEQS : ".$info[2]." sequence(s)\n";
infoprint " +-- NB COLS : ".$info[3]." column(s)\n";
infoprint " +-- CARDINALITY : ".$info[4]." distinct values\n";
infoprint " +-- NB ROWS : ".$info[5]." rows\n";
infoprint " +-- SELECTIVITY : ".$info[6]."%\n";
}
}
# Take the two recommendation arrays and display them at the end of the output
sub make_recommendations {