Resolví este problema con los siguientes pasos:
1.- caída de la tabla customer_grid_flat
2.- Volver a crear la tabla:
CREAR TABLA SI NO EXISTE customer_grid_flat(
entity_idint NO FIRMADO NO NULL COMENTARIO 'Entidad ID',
nametexto NULL COMMENT 'Nombre',
emailvarchar (255) NULL COMMENT 'Correo electrónico',
group_idint NULL COMMENT 'Group_id',
created_atmarca de tiempo NULL default NULL COMMENT 'Created_at',
website_idint COMENTARIO NULL 'Website_id',
confirmationvarchar (255) COMENTARIO NULL 'Confirmación',
created_intexto COMENTARIO NULL 'Created_in',
dobfecha COMENTARIO NULL 'Dob',
genderint COMENTARIO NULL 'Sexo',
taxvatvarchar (255) COMENTARIO NULL 'Taxvat',
lock_expiresmarca de tiempo NULL default COMENTARIO NULO 'Lock_expires',
shipping_fulltexto COMENTARIO NULO 'Shipping_full',
billing_fulltexto COMENTARIO NULO '
Billing_full ', billing_firstnamevarchar (255) COMENTARIO NULO' Billing_firstname ',
billing_lastnamevarchar (255) COMENTARIO NULO 'Billing_lastname',
billing_telephonevarchar (255) COMENTARIO NULO 'Billing_telephone',
billing_postcodevarchar (255) COMENTARIO NULO 'Billing_postcode',
billing_country_idvarchar (255) COMENTARIO NULO 'Billing_country_id',
billing_regionvarchar (255) COMENTARIO NULO 'Billing_region',
billing_streetvarchar (255) COMENTARIO NULO 'Billing_street',
billing_cityvarchar (255) COMENTARIO NULO 'Billing_city',
billing_faxvarchar (255) COMENTARIO NULO 'Billing_fax',
billing_vat_idvarchar (255) COMENTARIO NULO 'Billing_vat_id',
billing_companyvarchar (255) COMENTARIO NULO 'Billing_company', CLAVE PRIMARIA ( entity_id), ÍNDICE CUSTOMER_GRID_FLAT_GROUP_ID( group_id), ÍNDICE CUSTOMER_GRID_FLAT_CREATED_AT( created_at), ÍNDICE CUSTOMER_GRID_FLAT_WEBSITE_ID( website_id), ÍNDICE CUSTOMER_GRID_FLAT_CONFIRMATION( confirmation),ÍNDICE CUSTOMER_GRID_FLAT_DOB( dob), ÍNDICECUSTOMER_GRID_FLAT_GENDER( gender), Índice CUSTOMER_GRID_FLAT_BILLING_COUNTRY_ID( billing_country_id), FULLTEXT FTI_8746F705702DD5F6D45B8C7CE7FE9F2F( name, email, created_in, taxvat, shipping_full, billing_full, billing_firstname, billing_lastname, billing_telephone, billing_postcode, billing_region, billing_city, billing_fax, billing_company)) COMENTARIO = 'customer_grid_flat' ENGINE = innodb charset = utf8 COLLATE = utf8_general_ci