Package org.elasticsearch.xpack.esql.datasources

Class FilterAdaptation

java.lang.Object

org.elasticsearch.xpack.esql.datasources.FilterAdaptation

public final class FilterAdaptation
extends Object

Format-agnostic utility for adapting pushed filter expressions to a specific file's column set.

In UNION_BY_NAME scenarios, different files may have different columns. When a pushed filter references a column absent from a file, the predicate must be simplified before re-translation to the format-specific filter (Parquet FilterPredicate, ORC SearchArgument).

Adaptation rules for missing columns (SQL three-valued logic):

• Value comparison on missing column → UNKNOWN → FALSE in WHERE → remove conjunct
• IS NULL on missing column → TRUE (all rows match) → remove conjunct (always true)
• IS NOT NULL on missing column → FALSE → remove conjunct (entire AND is false)
• AND(A, B): if either is null (FALSE) → null; if either is TRUE → other side
• OR(A, B): if either is TRUE → TRUE; if one is null → other side
• NOT(child): if child is null → TRUE; if child is TRUE → null

RECHECK semantics guarantee correctness: the adapted filter only affects I/O optimization (row-group/stripe skipping), never row-level correctness.

Method Summary

Modifier and Type	Method	Description
static List<Expression>	adaptFilterForFile(List<Expression> filterConjuncts, Set<String> fileColumnNames)	Adapts pushed filter conjuncts for a specific file's column set.
static List<Expression>	adaptFilterForFile(List<Expression> filterConjuncts, Set<String> fileColumnNames, Map<String,DataType> fileColumnTypes)	Adapts pushed filter conjuncts for a specific file's column set and types.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

adaptFilterForFile

public static List<Expression> adaptFilterForFile(List<Expression> filterConjuncts,
 Set<String> fileColumnNames)

Adapts pushed filter conjuncts for a specific file's column set. Removes or simplifies predicates on columns absent from the file.

Parameters:

filterConjuncts - AND-separated pushed expressions (same contract as FilterPushdownSupport.pushFilters(java.util.List<org.elasticsearch.xpack.esql.core.expression.Expression>) input)

fileColumnNames - names of columns present in this file's schema

Returns:

adapted conjuncts; empty list means no pushdown for this file

adaptFilterForFile

public static List<Expression> adaptFilterForFile(List<Expression> filterConjuncts,
 Set<String> fileColumnNames,
 Map<String,DataType> fileColumnTypes)

Adapts pushed filter conjuncts for a specific file's column set and types. Handles both missing columns and type-widened columns.

When a column exists in the file with a narrower type than the unified schema (e.g., INTEGER in file vs LONG in unified), filter literals are downcast to the file's native type for optimal row-group/stripe skipping. Literals that overflow the narrower range are statically resolved based on the comparison operator.

Parameters:

filterConjuncts - AND-separated pushed expressions

fileColumnNames - names of columns present in this file's schema

fileColumnTypes - file-local types for columns that differ from the unified schema; columns not in this map are assumed to match the unified type

Returns:

adapted conjuncts; empty list means no pushdown for this file