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name: trino-to-hive-migration description: Convert Trino queries to Hive when memory errors occur. Covers syntax differences (td_time_string→TD_TIME_FORMAT, REGEXP_LIKE→RLIKE, ARRAY_AGG→COLLECT_LIST) and engine selection.

Trino to Hive Migration

When to Migrate

Use Hive when Trino fails with:

• Query exceeded per-node memory limit
• Query exceeded distributed memory limit
• Processing > 1 month of data, complex multi-way JOINs, high cardinality GROUP BY

Syntax Conversion

Trino	Hive
td_time_string(time, 'd!', 'JST')	TD_TIME_FORMAT(time, 'yyyy-MM-dd', 'JST')
approx_distinct(col)	approx_distinct(col) (Hivemall - compatible!)
approx_percentile(col, 0.95)	percentile(col, 0.95)
array_agg(col)	collect_list(col)
string_agg(col, ',')	concat_ws(',', collect_list(col))
regexp_like(col, 'pattern')	col rlike 'pattern'
Automatic small table join	/*+ MAPJOIN(t) */

Example Migration

Trino (fails with memory error):

select
  td_time_string(time, 'd!', 'JST') as date,
  approx_distinct(session_id) as sessions
from events
where td_time_range(time, '2024-01-01', '2024-12-31')
group by td_time_string(time, 'd!', 'JST')

Hive (works):

select
  TD_TIME_FORMAT(time, 'yyyy-MM-dd', 'JST') as date,
  approx_distinct(session_id) as sessions
from events
where td_time_range(time, '2024-01-01', '2024-12-31', 'JST')
group by TD_TIME_FORMAT(time, 'yyyy-MM-dd', 'JST')

Engine Selection

In Digdag:

+query_trino:
  td>: queries/analysis.sql
  engine: presto

+query_hive:
  td>: queries/analysis.sql
  engine: hive

In TD Toolbelt:

td query -d database_name -T presto "SELECT ..."
td query -d database_name -T hive "SELECT ..."

Performance Tips for Hive

-- MAPJOIN hint for small tables
select /*+ MAPJOIN(small_table) */ *
from large_table l
join small_table s on l.id = s.id

-- Process in chunks for very large datasets
where td_interval(time, '-1d', 'JST')  -- Daily instead of yearly

Typical Timeline

• Trino: Fails after 5 min with memory error
• Hive: Completes in 20-30 min successfully