============= Release 0.174

General Changes

• Fix correctness issue for correlated subqueries containing a LIMIT clause.
• Fix query failure when :func:!reduce function is used with lambda expressions containing :func:!array_sort, :func:!shuffle, :func:!reverse, :func:!array_intersect, :func:!arrays_overlap, :func:!concat (for arrays) or :func:!map_concat.
• Fix a bug that causes underestimation of the amount of memory used by :func:!max_by, :func:!min_by, :func:!max, :func:!min, and :func:!arbitrary aggregations over varchar/varbinary columns.
• Fix a memory leak in the coordinator that causes long-running queries in highly loaded clusters to consume unnecessary memory.
• Improve performance of aggregate window functions.
• Improve parallelism of queries involving GROUPING SETS, CUBE or ROLLUP.
• Improve parallelism of UNION queries.
• Filter and projection operations are now always processed columnar if possible, and Presto will automatically take advantage of dictionary encodings where effective. The processing_optimization session property and optimizer.processing-optimization configuration option have been removed.
• Add support for escaped unicode sequences in string literals.
• Add :doc:/sql/show-grants and information_schema.table_privileges table.

Hive Changes

• Change default value of hive.metastore-cache-ttl and hive.metastore-refresh-interval to 0 to disable cross-transaction metadata caching.

Web UI changes

• Fix ES6 compatibility issue with older browsers.
• Display buffered bytes for every stage in the live plan UI.

SPI changes

• Add support for retrieving table grants.
• Rename SPI access control check from checkCanShowTables to checkCanShowTablesMetadata, which is used for both :doc:/sql/show-tables and :doc:/sql/show-grants.