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Dont use cursor for getting plans

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Cursors cause bug in Pg15
This commit is contained in:
Hubert depesz Lubaczewski 2022-03-07 13:15:51 +01:00
parent 23f69af2d8
commit 5492f6a2b8
1 changed files with 12 additions and 9 deletions
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15
scripts/find_interesting_plans
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@ -68,11 +68,12 @@ for my $partno ( 0 .. $#{ $partitions } ) {
my $errors = 0;
my $interesting = 0;
my $query = sprintf "select id, plan FROM %s WHERE is_public and NOT is_deleted and NOT is_anonymized and plan ~ 'actual time=[0-9]'", $part;
$dbh->do( "DECLARE csr CURSOR FOR $query" );
my $prev_id = '';
my $query = sprintf "select id, plan FROM %s WHERE is_public and NOT is_deleted and NOT is_anonymized and plan ~ 'actual time=[0-9]' AND id > ? order by ID ASC LIMIT 100", $part;
while ( 1 ) {
my $rows = $dbh->selectall_arrayref( 'FETCH 100 FROM csr', { 'Slice' => {} } );
my $rows = $dbh->selectall_arrayref( $query, { 'Slice' => {} }, $prev_id );
last if 0 == scalar @{ $rows };
$prev_id = $rows->[ -1 ]->{ 'id' };
for my $row ( @{ $rows } ) {
$seen++;
my $explain;
@ -112,6 +113,7 @@ exit;
sub output_lines {
my ( $id, $plan ) = @_;
my $ret = [];
my $plan_len = length( $plan->source );
for my $node ( $plan->top_node, $plan->top_node->all_recursive_subnodes ) {
next unless $node->estimated_row_width;
@ -120,16 +122,17 @@ sub output_lines {
next unless $node->extra_info;
# At least 3 pages worth of data is returned
next unless $node->total_rows * $node->estimated_row_width > 3 * 8192;
next unless ( $node->total_rows + $node->total_rows_removed ) * $node->estimated_row_width > 3 * 8192;
# At least 90% of rows were removed
next unless $node->total_rows_removed > 9 * $node->total_rows;
next unless $node->total_rows_removed > 2 * $node->total_rows;
my @filter_lines = grep { /^Filter:/ } @{ $node->extra_info };
# There are filter expressions
next if 0 == scalar @filter_lines;
push @{ $ret }, map { [ $id, $node->id, $node->type, $node->estimated_row_width, $node->total_rows, $node->total_rows_removed, $_ ] } @filter_lines;
push @{ $ret }, map { [ $id, $plan_len, $node->type, $_ ] } @filter_lines;
}
return $ret;
}