diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index 9c4d7e0..2fb70ac 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -1,4 +1,4 @@
-<?php
+=<?php
 /**
  * CodeIgniter
  *
@@ -1480,18 +1480,18 @@
 				? '\s+'.preg_quote(trim(sprintf($this->_like_escape_str, $this->_like_escape_chr)), '/')
 				: '';
 			$_operators = array(
-				'\s*(?:<|>|!)?=\s*',		// =, <=, >=, !=
-				'\s*<>?\s*',			// <, <>
-				'\s*>\s*',			// >
-				'\s+IS NULL',			// IS NULL
-				'\s+IS NOT NULL',		// IS NOT NULL
-				'\s+EXISTS\s*\([^\)]+\)',	// EXISTS(sql)
-				'\s+NOT EXISTS\s*\([^\)]+\)',	// NOT EXISTS(sql)
-				'\s+BETWEEN\s+\S+\s+AND\s+\S+',	// BETWEEN value AND value
-				'\s+IN\s*\([^\)]+\)',		// IN(list)
-				'\s+NOT IN\s*\([^\)]+\)',	// NOT IN (list)
-				'\s+LIKE\s+\S+'.$_les,		// LIKE 'expr'[ ESCAPE '%s']
-				'\s+NOT LIKE\s+\S+'.$_les	// NOT LIKE 'expr'[ ESCAPE '%s']
+				'\s*(?:<|>|!)?=\s*',             // =, <=, >=, !=
+				'\s*<>?\s*',                     // <, <>
+				'\s*>\s*',                       // >
+				'\s+IS NULL',                    // IS NULL
+				'\s+IS NOT NULL',                // IS NOT NULL
+				'\s+EXISTS\s*\([^\)]+\)',        // EXISTS(sql)
+				'\s+NOT EXISTS\s*\([^\)]+\)',    // NOT EXISTS(sql)
+				'\s+BETWEEN\s+\S+\s+AND\s+\S+',  // BETWEEN value AND value
+				'\s+IN\s*\([^\)]+\)',            // IN(list)
+				'\s+NOT IN\s*\([^\)]+\)',        // NOT IN (list)
+				'\s+LIKE\s+\S.*('.$_les.')?',    // LIKE 'expr'[ ESCAPE '%s']
+				'\s+NOT LIKE\s+\S.*('.$_les.')?' // NOT LIKE 'expr'[ ESCAPE '%s']
 			);
 
 		}
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index bdde1ca..00d992a 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -22,6 +22,7 @@
 -  Fixed a bug (#4065) - :doc:`Database <database/index>` method ``protect_identifiers()`` treats a traling space as an alias separator if the input doesn't contain ' AS '.
 -  Fixed a bug (#4066) - :doc:`Cache Library <libraries/caching>` couldn't fallback to a backup driver if the primary one is Memcache(d) or Redis.
 -  Fixed a bug (#4073) - :doc:`Email Library <libraries/email>` method ``send()`` could return TRUE in case of an actual failure when an SMTP command fails.
+-  Fixed a bug (#4086) - :doc:`Query Builder <database/query_builder>` didn't apply *dbprefix* to LIKE conditions if the pattern included spaces.
 
 Version 3.0.1
 =============