Mark the order_hacks-injected ORDER BY SqlLiteral as retryable#2770
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`Arel::Visitors::OracleCommon#order_hacks` rewrites the outer ORDER
BY of `DISTINCT ... FIRST_VALUE(...)` queries (Oracle's
`columns_for_distinct` rewrite for ordering on columns outside the
SELECT list) by pushing `Nodes::SqlLiteral.new("alias_N__ DESC NULLS
...")` back into `o.orders`. `SqlLiteral` defaults to
`retryable: false`, and `visit_Arel_Nodes_SqlLiteral` runs
`collector.retryable &&= o.retryable`, so this single literal flips
the whole SELECT's `collector.retryable` to false even though the
query is a plain idempotent SELECT.
The bug is the same shape as the ROWNUM `SqlLiteral` issue fixed in
rsim#2766 — a visitor-internal `SqlLiteral` defeating AR's
`with_raw_connection(allow_retry: true)`. Both `Arel::Visitors::Oracle`
(pre-12c) and `Arel::Visitors::Oracle12` route through the same
`order_hacks` helper, so DISTINCT queries that hit this branch on
either visitor are affected.
Pass `retryable: true` so the rewrite is neutral on retryability,
matching the upstream Rails convention for visitor-injected
`SqlLiteral` (see `Arel::Visitors::MySQL` line 30/106:
`o.froms ||= Arel.sql("DUAL", retryable: true)` and the
`Arel.sql(quote_column_name(...), retryable: true)` projection
rewrite).
Add a regression spec in `arel/oracle_spec.rb` that builds the
DISTINCT+FIRST_VALUE shape, runs it through the visitor with a
collector preset to `retryable = true` (matching AR's
`to_sql_and_binds` preamble), and asserts the collector still
reports `retryable` true after compilation.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
Companion to #2766.
Arel::Visitors::OracleCommon#order_hacksrewrites the outerORDER BYofDISTINCT ... FIRST_VALUE(...)queries by pushingNodes::SqlLiteral.new("alias_N__ DESC NULLS ...")intoo.orders.SqlLiteraldefaults toretryable: false, andvisit_Arel_Nodes_SqlLiteralrunscollector.retryable &&= o.retryable, so this single literal flips the whole SELECT'scollector.retryableto false.Both
Arel::Visitors::Oracle(pre-12c) andArel::Visitors::Oracle12route through the sameorder_hackshelper, so DISTINCT-with-outside-order queries on either visitor are affected. AR core'swith_raw_connection(allow_retry: true)readscollector.retryableback intoallow_retry, so the practical fallout is that those SELECTs miss the AR-level reconnect-and-retry layer even though they are plain idempotent SELECTs.Pass
retryable: trueso the rewrite is neutral on retryability. This matches the upstream Rails convention for visitor-injectedSqlLiteral:Arel::Visitors::MySQLline 30 doeso.froms ||= Arel.sql("DUAL", retryable: true)and line 106 does the same for projection rewrites.Adds a regression spec in
arel/oracle_spec.rbthat builds the DISTINCT+FIRST_VALUE shape, runs it through the visitor with a collector preset toretryable = true(matching AR'sto_sql_and_bindspreamble), and asserts the collector still reportsretryabletrue after compilation.Test plan
BUNDLE_ONLY=rubocop bundle exec rubocop— clean (95 files, 0 offenses)test/test_11g—arel/oracle_spec.rbexercises the visitor in both versions viaOracleCommon