Core: Fix namespace SQL statement using ESCAPE character that works w…

…ith MySQL/PostgreSQL (#10167) (#10169)

Co-authored-by: Chauncy <[email protected]>

core/src/main/java/org/apache/iceberg/jdbc/JdbcUtil.java

@@ -335,7 +335,7 @@ enum SchemaVersion {
           + TABLE_NAMESPACE
           + " = ? OR "
           + TABLE_NAMESPACE
-          + " LIKE ? ESCAPE '\\')"
+          + " LIKE ? ESCAPE '!')"
           + " LIMIT 1";
   static final String LIST_NAMESPACES_SQL =
       "SELECT DISTINCT "
@@ -426,7 +426,7 @@ enum SchemaVersion {
           + NAMESPACE_NAME
           + " = ? OR "
           + NAMESPACE_NAME
-          + " LIKE ? ESCAPE '\\' "
+          + " LIKE ? ESCAPE '!' "
           + " ) ";
   static final String INSERT_NAMESPACE_PROPERTIES_SQL =
       "INSERT INTO "
@@ -783,7 +783,7 @@ static boolean namespaceExists(
     // when namespace has sub-namespace then additionally checking it with LIKE statement.
     // catalog.db can exists as: catalog.db.ns1 or catalog.db.ns1.ns2
     String namespaceStartsWith =
-        namespaceEquals.replace("\\", "\\\\").replace("_", "\\_").replace("%", "\\%") + ".%";
+        namespaceEquals.replace("!", "!!").replace("_", "!_").replace("%", "!%") + ".%";
     if (exists(connections, GET_NAMESPACE_SQL, catalogName, namespaceEquals, namespaceStartsWith)) {
       return true;
     }