escape quote in mapfile layer

I'm using mapserver 6 with mysql 5.5. It work like a charme, almost...

The layer part of my mapfile is

LAYER
    NAME "monsatR_mySQL"
    TYPE POINT
    STATUS ON
    CONNECTIONTYPE OGR
    CONNECTION "MYSQL:monasteres,host=1.1.1.1,port=3306,user=Foo,password=p4ssW0rd"
    DATA "SELECT a.*,b.id_etab,b.nom_usuel FROM t_geom_points as a LEFT JOIN t_etab as b ON a.id_etab = b.id_etab"
    DUMP TRUE ## REQUIRED


    METADATA
      "wfs_title" "monastR" ##required
      "wfs_srs"    "EPSG:4326" ##REQUIRED
      "gml_include_items" "all" ## Optional (serves all attributes for layer)
      "gml_featureid"     "FID" ## REQUIRED
      "wfs_enable_request" "*"
      "wfs_getfeature_formatlist" "OGRGeoJSON"
    END
    PROJECTION
      #"init=epsg:3857" ##recommended
      "init=epsg:4326"
    END
    TRANSPARENCY 50
    CLASS
      NAME "monastR français"
    END   
  END #LAYER

As you can seen, the output is a geoJson. My problem come from nom_usuel column where some characteres are single quote like Saint-Pierre de l'Isle... Single quote are misunderstand in geoJson ...

how can I escape single quotes ? I have seen some information in the mapserver documentation, but I'm not abble to build the solution!

help would be appreciated

EDIT as Laurent Jégou proposed I have tried with SELECT a.*,b.id_etab,REPLACE(nom_usuel, '\'',chr(39)) FROM t_geom_points as a LEFT JOIN t_etab as b ON a.id_etab = b.id_etab

But it returns

<ows:ExceptionReport version="1.1.0" language="en-US" xsi:schemaLocation="http://ift.tt/1ikcaPe http://ift.tt/1LhZrq2"><ows:Exception exceptionCode="NoApplicableCode" locator="mapserv">   <ows:ExceptionText>msWFSGetFeature(): WFS server error. ms_error->code not found
msOGRFileOpen(): OGR error. ExecuteSQL(SELECT a.*,b.id_etab,REPLACE(nom_usuel, ''',chr(39)) FROM t_geom_points as a LEFT JOIN t_etab as b ON a.id_etab = b.id_etab) failed.
MySQL error message:You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '''',chr(39)) FROM t_geom_points as a LEFT JOIN t_etab as b ON a.id_etab = b.id_e' at line 1 Description: SELECT a.*,b.id_etab,REPLACE(nom_usuel, ''',chr(39)) FROM t_geom_points as a LEFT JOIN t_etab as b ON a.id_etab = b.id_etab
msOGRFileOpen(): OGR error. ExecuteSQL(SELECT a.*,b.id_etab,REPLACE(nom_usuel, ''',chr(39)) FROM t_geom_points as a LEFT JOIN t_etab as b ON a.id_etab = b.id_etab) failed.
MySQL error message:You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '''',chr(39)) FROM t_geom_points as a LEFT JOIN t_etab as b ON a.id_etab = b.id_e' at line 1 Description: SELECT a.*,b.id_etab,REPLACE(nom_usuel, ''',chr(39)) FROM t_geom_points as a LEFT JOIN t_etab as b ON a.id_etab = b.id_etab</ows:ExceptionText></ows:Exception></ows:ExceptionReport>