diff --git a/ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/AbstractFilterStringColLikeStringScalar.java b/ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/AbstractFilterStringColLikeStringScalar.java
index 542c6b381493..f26c19103876 100644
--- a/ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/AbstractFilterStringColLikeStringScalar.java
+++ b/ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/AbstractFilterStringColLikeStringScalar.java
@@ -419,7 +419,7 @@ protected static final class ComplexChecker implements Checker {
     FastUTF8Decoder decoder;
 
     public ComplexChecker(String pattern) {
-      compiledPattern = Pattern.compile(pattern);
+      compiledPattern = Pattern.compile(pattern, Pattern.DOTALL);
       matcher = compiledPattern.matcher("");
       decoder = new FastUTF8Decoder();
     }
diff --git a/ql/src/test/org/apache/hadoop/hive/ql/exec/vector/expressions/TestVectorStringExpressions.java b/ql/src/test/org/apache/hadoop/hive/ql/exec/vector/expressions/TestVectorStringExpressions.java
index 22ac562c43ab..001996182c40 100644
--- a/ql/src/test/org/apache/hadoop/hive/ql/exec/vector/expressions/TestVectorStringExpressions.java
+++ b/ql/src/test/org/apache/hadoop/hive/ql/exec/vector/expressions/TestVectorStringExpressions.java
@@ -4407,6 +4407,33 @@ public void testStringLikePatternType() throws HiveException {
         expr.checker.getClass());
   }
 
+  // Regression: vec ComplexChecker must apply Pattern.DOTALL (mirroring HIVE-22008).
+  @Test
+  public void testStringLikeComplexCheckerMultiLine() throws HiveException {
+    VectorizedRowBatch batch = new VectorizedRowBatch(1);
+    BytesColumnVector col = new BytesColumnVector();
+    batch.cols[0] = col;
+    byte[] rowA = "first\nsecond".getBytes(StandardCharsets.UTF_8);
+    byte[] rowB = "first_second\nthird".getBytes(StandardCharsets.UTF_8);
+    col.setRef(0, rowA, 0, rowA.length);
+    col.setRef(1, rowB, 0, rowB.length);
+    col.isNull[0] = false;
+    col.isNull[1] = false;
+    col.noNulls = true;
+    batch.size = 2;
+
+    FilterStringColLikeStringScalar expr =
+        new FilterStringColLikeStringScalar(0, "%first_second%".getBytes(StandardCharsets.UTF_8));
+    expr.transientInit(hiveConf);
+    Assert.assertEquals(FilterStringColLikeStringScalar.ComplexChecker.class,
+        expr.checker.getClass());
+
+    expr.evaluate(batch);
+
+    // Both rows must survive the LIKE filter.
+    Assert.assertEquals(2, batch.size);
+  }
+
   @Test
   public void testStringLikeMultiByte() throws HiveException {
     FilterStringColLikeStringScalar expr;
diff --git a/ql/src/test/queries/clientpositive/udf_like.q b/ql/src/test/queries/clientpositive/udf_like.q
index a4a7251bf28b..89364aee78fc 100644
--- a/ql/src/test/queries/clientpositive/udf_like.q
+++ b/ql/src/test/queries/clientpositive/udf_like.q
@@ -28,3 +28,36 @@ FROM src tablesample (1 rows);
 CREATE TEMPORARY TABLE SplitLines(`id` string) STORED AS ORC;
 INSERT INTO SplitLines SELECT 'withdraw\ncash';
 SELECT `id` LIKE '%withdraw%cash' FROM SplitLines ;
+
+CREATE TABLE SplitLinesUnderscore (q STRING) STORED AS ORC;
+INSERT INTO SplitLinesUnderscore
+  SELECT 'first\nsecond' UNION ALL SELECT 'first_second\nthird';
+SELECT count(*) FROM SplitLinesUnderscore WHERE q LIKE '%first_second%';
+
+-- Repeat with vectorization off to ensure consistency either way
+set hive.vectorized.execution.enabled=false;
+
+DESCRIBE FUNCTION like;
+DESCRIBE FUNCTION EXTENDED like;
+
+EXPLAIN
+SELECT '_%_' LIKE '%\_\%\_%', '__' LIKE '%\_\%\_%', '%%_%_' LIKE '%\_\%\_%', '%_%_%' LIKE '%\%\_\%',
+  '_%_' LIKE '\%\_%', '%__' LIKE '__\%%', '_%' LIKE '\_\%\_\%%', '_%' LIKE '\_\%_%',
+  '%_' LIKE '\%\_', 'ab' LIKE '\%\_', 'ab' LIKE '_a%', 'ab' LIKE 'a','ab' LIKE '','' LIKE ''
+FROM src WHERE src.key = 86;
+
+SELECT '_%_' LIKE '%\_\%\_%', '__' LIKE '%\_\%\_%', '%%_%_' LIKE '%\_\%\_%', '%_%_%' LIKE '%\%\_\%',
+  '_%_' LIKE '\%\_%', '%__' LIKE '__\%%', '_%' LIKE '\_\%\_\%%', '_%' LIKE '\_\%_%',
+  '%_' LIKE '\%\_', 'ab' LIKE '\%\_', 'ab' LIKE '_a%', 'ab' LIKE 'a','ab' LIKE '','' LIKE ''
+FROM src WHERE src.key = 86;
+
+
+SELECT '1+2' LIKE '_+_',
+       '1+2' LIKE '1+_',
+       '112' LIKE '1+_',
+       '|||' LIKE '|_|',
+       '+++' LIKE '1+_'
+FROM src tablesample (1 rows);
+
+SELECT `id` LIKE '%withdraw%cash' FROM SplitLines;
+SELECT count(*) FROM SplitLinesUnderscore WHERE q LIKE '%first_second%';
diff --git a/ql/src/test/results/clientpositive/llap/udf_like.q.out b/ql/src/test/results/clientpositive/llap/udf_like.q.out
index 3c86fa7feecf..f8a8ac6e1ce2 100644
--- a/ql/src/test/results/clientpositive/llap/udf_like.q.out
+++ b/ql/src/test/results/clientpositive/llap/udf_like.q.out
@@ -107,3 +107,132 @@ POSTHOOK: type: QUERY
 POSTHOOK: Input: default@splitlines
 #### A masked pattern was here ####
 true
+PREHOOK: query: CREATE TABLE SplitLinesUnderscore (q STRING) STORED AS ORC
+PREHOOK: type: CREATETABLE
+PREHOOK: Output: database:default
+PREHOOK: Output: default@SplitLinesUnderscore
+POSTHOOK: query: CREATE TABLE SplitLinesUnderscore (q STRING) STORED AS ORC
+POSTHOOK: type: CREATETABLE
+POSTHOOK: Output: database:default
+POSTHOOK: Output: default@SplitLinesUnderscore
+PREHOOK: query: INSERT INTO SplitLinesUnderscore
+  SELECT 'first\nsecond' UNION ALL SELECT 'first_second\nthird'
+PREHOOK: type: QUERY
+PREHOOK: Input: _dummy_database@_dummy_table
+PREHOOK: Output: default@splitlinesunderscore
+POSTHOOK: query: INSERT INTO SplitLinesUnderscore
+  SELECT 'first\nsecond' UNION ALL SELECT 'first_second\nthird'
+POSTHOOK: type: QUERY
+POSTHOOK: Input: _dummy_database@_dummy_table
+POSTHOOK: Output: default@splitlinesunderscore
+POSTHOOK: Lineage: splitlinesunderscore.q SCRIPT []
+PREHOOK: query: SELECT count(*) FROM SplitLinesUnderscore WHERE q LIKE '%first_second%'
+PREHOOK: type: QUERY
+PREHOOK: Input: default@splitlinesunderscore
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT count(*) FROM SplitLinesUnderscore WHERE q LIKE '%first_second%'
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@splitlinesunderscore
+#### A masked pattern was here ####
+2
+PREHOOK: query: DESCRIBE FUNCTION like
+PREHOOK: type: DESCFUNCTION
+POSTHOOK: query: DESCRIBE FUNCTION like
+POSTHOOK: type: DESCFUNCTION
+like(str, pattern) - Checks if str matches pattern
+PREHOOK: query: DESCRIBE FUNCTION EXTENDED like
+PREHOOK: type: DESCFUNCTION
+POSTHOOK: query: DESCRIBE FUNCTION EXTENDED like
+POSTHOOK: type: DESCFUNCTION
+like(str, pattern) - Checks if str matches pattern
+Example:
+  > SELECT a.* FROM srcpart a WHERE a.hr like '%2' LIMIT 1;
+  27      val_27  2008-04-08      12
+Function class:org.apache.hadoop.hive.ql.udf.UDFLike
+Function type:BUILTIN
+PREHOOK: query: EXPLAIN
+SELECT '_%_' LIKE '%\_\%\_%', '__' LIKE '%\_\%\_%', '%%_%_' LIKE '%\_\%\_%', '%_%_%' LIKE '%\%\_\%',
+  '_%_' LIKE '\%\_%', '%__' LIKE '__\%%', '_%' LIKE '\_\%\_\%%', '_%' LIKE '\_\%_%',
+  '%_' LIKE '\%\_', 'ab' LIKE '\%\_', 'ab' LIKE '_a%', 'ab' LIKE 'a','ab' LIKE '','' LIKE ''
+FROM src WHERE src.key = 86
+PREHOOK: type: QUERY
+PREHOOK: Input: default@src
+#### A masked pattern was here ####
+POSTHOOK: query: EXPLAIN
+SELECT '_%_' LIKE '%\_\%\_%', '__' LIKE '%\_\%\_%', '%%_%_' LIKE '%\_\%\_%', '%_%_%' LIKE '%\%\_\%',
+  '_%_' LIKE '\%\_%', '%__' LIKE '__\%%', '_%' LIKE '\_\%\_\%%', '_%' LIKE '\_\%_%',
+  '%_' LIKE '\%\_', 'ab' LIKE '\%\_', 'ab' LIKE '_a%', 'ab' LIKE 'a','ab' LIKE '','' LIKE ''
+FROM src WHERE src.key = 86
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@src
+#### A masked pattern was here ####
+STAGE DEPENDENCIES:
+  Stage-0 is a root stage
+
+STAGE PLANS:
+  Stage: Stage-0
+    Fetch Operator
+      limit: -1
+      Processor Tree:
+        TableScan
+          alias: src
+          filterExpr: (UDFToDouble(key) = 86.0D) (type: boolean)
+          Filter Operator
+            predicate: (UDFToDouble(key) = 86.0D) (type: boolean)
+            Select Operator
+              expressions: true (type: boolean), false (type: boolean), true (type: boolean), true (type: boolean), false (type: boolean), false (type: boolean), false (type: boolean), false (type: boolean), true (type: boolean), false (type: boolean), false (type: boolean), false (type: boolean), false (type: boolean), true (type: boolean)
+              outputColumnNames: _col0, _col1, _col2, _col3, _col4, _col5, _col6, _col7, _col8, _col9, _col10, _col11, _col12, _col13
+              ListSink
+
+PREHOOK: query: SELECT '_%_' LIKE '%\_\%\_%', '__' LIKE '%\_\%\_%', '%%_%_' LIKE '%\_\%\_%', '%_%_%' LIKE '%\%\_\%',
+  '_%_' LIKE '\%\_%', '%__' LIKE '__\%%', '_%' LIKE '\_\%\_\%%', '_%' LIKE '\_\%_%',
+  '%_' LIKE '\%\_', 'ab' LIKE '\%\_', 'ab' LIKE '_a%', 'ab' LIKE 'a','ab' LIKE '','' LIKE ''
+FROM src WHERE src.key = 86
+PREHOOK: type: QUERY
+PREHOOK: Input: default@src
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT '_%_' LIKE '%\_\%\_%', '__' LIKE '%\_\%\_%', '%%_%_' LIKE '%\_\%\_%', '%_%_%' LIKE '%\%\_\%',
+  '_%_' LIKE '\%\_%', '%__' LIKE '__\%%', '_%' LIKE '\_\%\_\%%', '_%' LIKE '\_\%_%',
+  '%_' LIKE '\%\_', 'ab' LIKE '\%\_', 'ab' LIKE '_a%', 'ab' LIKE 'a','ab' LIKE '','' LIKE ''
+FROM src WHERE src.key = 86
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@src
+#### A masked pattern was here ####
+true	false	true	true	false	false	false	false	true	false	false	false	false	true
+PREHOOK: query: SELECT '1+2' LIKE '_+_',
+       '1+2' LIKE '1+_',
+       '112' LIKE '1+_',
+       '|||' LIKE '|_|',
+       '+++' LIKE '1+_'
+FROM src tablesample (1 rows)
+PREHOOK: type: QUERY
+PREHOOK: Input: default@src
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT '1+2' LIKE '_+_',
+       '1+2' LIKE '1+_',
+       '112' LIKE '1+_',
+       '|||' LIKE '|_|',
+       '+++' LIKE '1+_'
+FROM src tablesample (1 rows)
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@src
+#### A masked pattern was here ####
+true	true	false	true	false
+PREHOOK: query: SELECT `id` LIKE '%withdraw%cash' FROM SplitLines
+PREHOOK: type: QUERY
+PREHOOK: Input: default@splitlines
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT `id` LIKE '%withdraw%cash' FROM SplitLines
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@splitlines
+#### A masked pattern was here ####
+true
+PREHOOK: query: SELECT count(*) FROM SplitLinesUnderscore WHERE q LIKE '%first_second%'
+PREHOOK: type: QUERY
+PREHOOK: Input: default@splitlinesunderscore
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT count(*) FROM SplitLinesUnderscore WHERE q LIKE '%first_second%'
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@splitlinesunderscore
+#### A masked pattern was here ####
+2