MySQL 8.0

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CREATE TABLE wph0_postmeta  (
  `id` INTEGER,
  `meta-key` VARCHAR(20),
  `meta-value` VARCHAR(20)
);

INSERT INTO wph0_postmeta 
  (`id`, `meta-key`, `meta-value`)
VALUES
  ('1', 'client', 'John'),
  ('1', 'bday', 'today'),
  ('1', 'descriptiuon', 'test'),
    ('2', 'client', 'Jerry'),
  ('2', 'bday', 'tomorrow'),
  ('2', 'descriptiuon', 'secondtest');
INSERT INTO wph0_postmeta 
  (`id`, `meta-key`, `meta-value`)
VALUES
  ('1', 'client', 'John'),
  ('1', 'bday', 'today'),
  ('1', 'descriptiuon', 'test'),
    ('2', 'client', 'Jerry'),
  ('2', 'bday', 'tomorrow'),
  ('2', 'descriptiuon', 'secondtest');
CREATE TABLE wph0_posts ( id INT, post_title varchar(20));
INSERT INTO wph0_posts VALUES (1,'Dr.Dr.'),(2,'Prof.Dr.Dr.')
SELECT t1.id,
t2.post_title
,MAX(IF(t1.`meta-key` = 'client',   t1.`meta-value`,NULL)) 'client'
,MAX(IF(t1.`meta-key` = 'bday',   t1.`meta-value`,NULL)) 'birthday'
,MAX(IF(t1.`meta-key` = 'descriptiuon',   t1.`meta-value`,NULL)) 'descriptiuon'
FROM wph0_postmeta t1 INNER JOIN wph0_posts t2 ON t1.id = t2.id
GROUP BY t1.id,t2.post_title


id
post_title
client
birthday
descriptiuon


1
Dr.Dr.
John
today
test

2
Prof.Dr.Dr.
Jerry
tomorrow
secondtest