Is it possible to use IF within the FROM in MySql?

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Is it possible to use IF within the FROM in MySql?

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#1 by (1 votes)
#2 by (0 votes)

-1

Could it be IF within FROM ? I searched but could not find anything about it.

Here is an example of what I want to do:

SELECT usuario.* FROM (
  SELECT
  IF( 
    (SELECT COUNT(*) FROM pessoa) > 0, 
    SELECT  FROM pessoa,
    SELECT * FROM clliente, 
  ) AS usuario
)

NOTE: Since the bank architecture was developed the worst way, I'm having to do some crazy SQL.

mysql sql

asked by anonymous 24.05.2016 / 22:13

2 answers

Count characters in a string from a search done in the string itself What Dlls Do I need to create a project with oracle in visual studio 2015?

score 1 · Answer 1

One solution might be to create a view

create or replace view v_pessoa_cliente
as
select cpf , nome from pessoa
union
select cpf,nome from cliente

In the application do

select *
from v_pessoa_cliente
where nome = 'Daniel Dutra'

score 0 · Answer 2

Simplifying this way would not solve your case?

SELECT IF(COUNT(p.*) > 0, p.*, c.*) as usuarios_maior_volume
FROM pessoas p, clientes c;

And to get global:

SELECT * FROM pessoas, clientes;

And to bring it all:

SELECT * FROM pessoas
union all
SELECT * FROM clientes;