mysql - How to select rows from a table that matches all the rows from a second table which has predicates? -

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i have 2 tables, transaction table , transaction property table follows.

transaction table 

create table `mydb`.`event` (   `id` int not null auto_increment,   `user` varchar(45) not null,   `type` int not null,    primary key (`id`));

property table

create table `mydb`.`event_property` (   `event_id` int not null,   `property_type` varchar(45) not null,   `value` varchar(45) not null,   primary key (`event_id`, `property_type`, `value`),   constraint `event_id`     foreign key (`event_id`)     references `mydb`.`event` (`id`)     on delete restrict     on update restrict);

a single event may have multiple properties. want select event has 2 properties values. how this?

you can group by , having:

select event_id event_property property_type in ('1', '2') group event_id having count(distinct property_type) = 2;

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