Um erro no Banco de Dados aconteceu

Error Number: 1327

Undeclared variable: index

SELECT gc_cntd.CN_IdCntd, gc_cntd.CN_Tit, gc_cntd.CN_Resm, gc_cntd.CN_ImgMini, gc_cntd.CN_DtCad FROM gc_cntd, gc_cntd_cat WHERE gc_cntd.CN_Sts = 'Sim' AND gc_cntd_cat.CC_IdCntd = gc_cntd.CN_IdCntd AND gc_cntd_cat.CC_IdCat = '1' GROUP BY gc_cntd.CN_IdCntd ORDER BY gc_cntd.CN_DtCad DESC LIMIT index.html, 15

Filename: models/Conteudo_site_model.php

Line Number: 99