From a86bca8c3e8aa134eb0f416e91f699be02b7d20c Mon Sep 17 00:00:00 2001
From: Julian Hyde <jhyde@apache.org>
Date: Tue, 9 Jan 2024 12:15:11 -0800
Subject: [PATCH] Revert [CALCITE-6180] Append possibility to escape backslash
 in LIKE with ESCAPE operator

---
 core/src/main/java/org/apache/calcite/runtime/Like.java        | 3 ---
 .../src/main/java/org/apache/calcite/test/SqlOperatorTest.java | 3 ---
 2 files changed, 6 deletions(-)

diff --git a/core/src/main/java/org/apache/calcite/runtime/Like.java b/core/src/main/java/org/apache/calcite/runtime/Like.java
index 865efcc8d3c..ac074afa3da 100644
--- a/core/src/main/java/org/apache/calcite/runtime/Like.java
+++ b/core/src/main/java/org/apache/calcite/runtime/Like.java
@@ -96,9 +96,6 @@ static String sqlToRegexLike(
             || (nextChar == escapeChar)) {
           javaPattern.append(nextChar);
           i++;
-        } else if (nextChar == '\\') {
-          javaPattern.append("\\\\");
-          i++;
         } else {
           throw invalidEscapeSequence(sqlPattern, i);
         }
diff --git a/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java b/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java
index 09311731dd2..c393a0f8486 100644
--- a/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java
+++ b/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java
@@ -3606,9 +3606,6 @@ static void checkRlikeFails(SqlOperatorFixture f) {
   @Test void testLikeEscape() {
     final SqlOperatorFixture f = fixture();
     f.setFor(SqlStdOperatorTable.LIKE, VmName.EXPAND);
-    f.checkBoolean("'a\\c' like 'a#\\c' escape '#'", true);
-    f.checkBoolean("'a\\\\c' like 'a#\\c' escape '#'", false);
-    f.checkBoolean("'a\\c' like 'a#\\\\c' escape '#'", false);
     f.checkBoolean("'a_c' like 'a#_c' escape '#'", true);
     f.checkBoolean("'axc' like 'a#_c' escape '#'", false);
     f.checkBoolean("'a_c' like 'a\\_c' escape '\\'", true);