Address PR feedback

expression/builtin_miscellaneous.go

@@ -204,10 +204,14 @@ func (b *builtinLockSig) evalInt(row chunk.Row) (int64, bool, error) {
 	}
 	// A timeout less than zero is expected to be treated as unlimited.
 	// Because of our implementation being based on pessimistic locks,
-	// We set the timeout to the maximum value of innodb_lock_wait_timeout.
-	if timeout < 0 {
-		timeout = int64(variable.GetSysVar("innodb_lock_wait_timeout").MaxValue)
-	}
+	// We can't have a timeout greater than innodb_lock_wait_timeout.
+	maxTimeout := int64(variable.GetSysVar("innodb_lock_wait_timeout").MaxValue)
+	if timeout < 0 || timeout > maxTimeout {
+		timeout = maxTimeout
+	}
+	// Lock names are case insensitive. Because we can't rely on collations
+	// being enabled on the internal table, we have to lower it.
+	lockName = strings.ToLower(lockName)
 	err = b.ctx.GetAdvisoryLock(lockName, timeout)
 	if err != nil {
 		switch err.(*terror.Error).Code() {
@@ -259,6 +263,9 @@ func (b *builtinReleaseLockSig) evalInt(row chunk.Row) (int64, bool, error) {
 	if err != nil {
 		return 0, isNull, err
 	}
+	// Lock names are case insensitive. Because we can't rely on collations
+	// being enabled on the internal table, we have to lower it.
+	lockName = strings.ToLower(lockName)
 	released := int64(0)
 	if b.ctx.ReleaseAdvisoryLock(lockName) {
 		released = 1

session/bootstrap.go

@@ -596,7 +596,7 @@ const (
 
 // currentBootstrapVersion is defined as a variable, so we can modify its value for testing.
 // please make sure this is the largest version
-var currentBootstrapVersion int64 = version86
+var currentBootstrapVersion int64 = version87
 
 var (
 	bootstrapVersion = []func(Session, int64){