How to perform an "IF" by SQL

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Hello, how can I do something similar to an if but by sql?
For example: There is a field in the database called dt_ini with no value so far.
I’d like to do, "If dt_ini == ' ' Insert into table (dt_ini) values ..."
Would have to make a query in the database to see the dt_ini is or has the null value if yes Insert into... else ...

mysql sql

  • Ever tried to make a insert-select?

  • I didn’t quite understand the purpose, but the condition is made by the case when: https://dev.mysql.com/doc/refman/5.7/en/case.html

  • 2

    If no SQL? Sorry if I’m talking nonsense, but a Where does not answer you?

  • Where... well thought out, I believe it suits me yes

2 answers

-1

Opa Mrvandaime, try to do the following,

INSERT INTO SUA_TABELA (dt_ini) VALUES WORTH WHERE DT_INI IS NULL;

OR

INSERT INTO SUA_TABELA (dt_ini) VALUES WORTH WHERE DT_INI = "";

  • This syntax is valid in MySQL? I’ve only seen at most insert-select with clause where

  • 1

    I do not think so: https://stackoverflow.com/questions/485039/mysql-insert-where-query

-1

Let me get this straight, do you want to update the dt_ini value of the table itself? if empty?

If so, try this:

UPDATE SUA_TABELA SET DT_INI = VALOR WHERE DT_INI IS NULL

If you are an Insert elsewhere, if dt_ini is empty, try:

INSERT INTO SUA_TABELA (CAMPOS) VALUES (VALORES) WHERE 1 IN (SELECT 1 FROM SUA_TABELA WHERE DT_INI IS NULL)
  • 1

    Have you tested this INSERT? I’ve never seen this syntax or found it in the documentation.]

  • Yes, I’ve used it a few times. In the documentation you’ll find talking about IN compared to another select. In this case, if select brings result, this will be the Insert trigger.

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