Question

I have this MySQL query and the syntax is correct, but when I want to see the view, the mysql process go to 100%.

CREATE OR REPLACE VIEW tx_oriconvenios_consultas AS
        SELECT conv.*, tipo.descripcion AS tipo_convenio, uni.nombre AS n_universidad, ciu.nombre AS n_ciudad, pais.cn_short_es AS n_pais, COUNT(hist.estado) AS n_estado
        FROM tx_unalori_convenio AS conv
        LEFT JOIN tx_unalori_historico as hist
        ON conv.uid = hist.convenio
        INNER JOIN tx_unalori_tipoconv as tipo
        ON conv.tipoconv = tipo.uid
        INNER JOIN tx_unalori_universidad as uni
        ON conv.universidad = uni.uid
        INNER JOIN tx_unalori_ciudad as ciu
        ON ciu.uid=uni.uid_ciudad
        INNER JOIN static_countries as pais
        ON pais.cn_iso_3 = ciu.pais
        GROUP BY conv.uid

If I remove:

INNER JOIN static_countries as pais
        ON pais.cn_iso_3 = ciu.pais

or:

 LEFT JOIN tx_unalori_historico as hist
    ON conv.uid = hist.convenio

Then I can enter to the view and see the registers.

I can’t understand why.

I really apreciate some explanation.

---

For those who asked, this is the structure of static_countries:

CREATE TABLE IF NOT EXISTS `static_countries` (
  `uid` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `pid` int(11) unsigned DEFAULT '0',
  `deleted` tinyint(4) NOT NULL DEFAULT '0',
  `cn_iso_2` char(2) DEFAULT '',
  `cn_iso_3` char(3) DEFAULT '',
  `cn_iso_nr` int(11) unsigned DEFAULT '0',
  `cn_parent_tr_iso_nr` int(11) unsigned DEFAULT '0',
  `cn_official_name_local` varchar(128) DEFAULT '',
  `cn_official_name_en` varchar(128) DEFAULT '',
  `cn_capital` varchar(45) DEFAULT '',
  `cn_tldomain` char(2) DEFAULT '',
  `cn_currency_iso_3` char(3) DEFAULT '',
  `cn_currency_iso_nr` int(10) unsigned DEFAULT '0',
  `cn_phone` int(10) unsigned DEFAULT '0',
  `cn_eu_member` tinyint(3) unsigned DEFAULT '0',
  `cn_address_format` tinyint(3) unsigned DEFAULT '0',
  `cn_zone_flag` tinyint(4) DEFAULT '0',
  `cn_short_local` varchar(70) DEFAULT '',
  `cn_short_en` varchar(50) DEFAULT '',
  `cn_uno_member` tinyint(3) unsigned DEFAULT '0',
  `cn_short_es` varchar(50) NOT NULL DEFAULT '',
  PRIMARY KEY (`uid`),
  UNIQUE KEY `uid` (`uid`)
) ENGINE=MyISAM  DEFAULT CHARSET=latin1 AUTO_INCREMENT=250 ;

And this of the tx_unalori_historico:

CREATE TABLE IF NOT EXISTS `tx_unalori_historico` (
  `uid` int(11) NOT NULL AUTO_INCREMENT,
  `pid` int(11) NOT NULL DEFAULT '0',
  `tstamp` int(11) NOT NULL DEFAULT '0',
  `crdate` int(11) NOT NULL DEFAULT '0',
  `cruser_id` int(11) NOT NULL DEFAULT '0',
  `deleted` tinyint(4) NOT NULL DEFAULT '0',
  `hidden` tinyint(4) NOT NULL DEFAULT '0',
  `be_users` int(11) NOT NULL DEFAULT '0',
  `convenio` int(11) NOT NULL DEFAULT '0',
  `estado` int(11) NOT NULL DEFAULT '0',
  `observaciones` text NOT NULL,
  PRIMARY KEY (`uid`),
  KEY `parent` (`pid`)
) ENGINE=MyISAM  DEFAULT CHARSET=latin1 AUTO_INCREMENT=3810 ;

Answer 1

Thanks @ypercube.

The problem was solved adding index keys to static_countries.cn_iso_3 and tx_unalori_ciudad.pais