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Use .execute to avoid any possibility of prepared statements (#5509) [deploy]

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rhymes 2020-01-14 19:23:32 +01:00 • committed by Molly Struve
parent 8f87f02978
commit 760d5ef325
1 changed files with 7 additions and 11 deletions
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18
app/models/application_record.rb
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@ -4,24 +4,20 @@ class ApplicationRecord < ActiveRecord::Base
QUERY_ESTIMATED_COUNT = <<~SQL.squish.freeze
SELECT (
(reltuples / GREATEST(relpages, 1)) *
(pg_relation_size($1) / (GREATEST(current_setting('block_size')::integer, 1)))
(pg_relation_size(?) / (GREATEST(current_setting('block_size')::integer, 1)))
)::bigint AS count
FROM pg_class WHERE relname = $2;
FROM pg_class WHERE relname = ?;
SQL
# Computes an estimated count of the number of rows using stats collected by VACUUM
# inspired by <https://www.citusdata.com/blog/2016/10/12/count-performance/#dup_counts_estimated_full>
# and <https://stackoverflow.com/a/48391562/4186181>
def self.estimated_count
query_name = "SQL COUNT ESTIMATE: #{table_name}"
table_name_attr = ActiveRecord::Relation::QueryAttribute.new(
"relname", table_name, ActiveRecord::Type::String.new
)
query = sanitize_sql_array([QUERY_ESTIMATED_COUNT, table_name, table_name])
result = connection.execute(query)
result = connection.exec_query(
QUERY_ESTIMATED_COUNT, query_name, [table_name_attr, table_name_attr]
)
result.first["count"]
count = result.first["count"]
result.clear # PG::Result is manually managed in memory, we need to release its resources
count
end
end