How to check if a character set exists in the table column?

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-1

I have the following table:

|id|nome                 |
|1 |Lucas Santos da Silva|
|2 |Igor Julião Gonçalves|
|3 |Mário Marques Silva  |
|4 |David Silva          |

How could I catch all the people who have Silva in the name?

$string = "Silva";
$sql = "SELECT * FROM usuarios WHERE nome IN('{$string}');
sql operator-like
  • 2

    I couldn’t use the operator LIKE?

  • Could inform which is the database, because there is an artificial that can significantly improve the query time and each BDMS implements it in a way.

  • the name of the bank is cde3.

  • It is difficult to present a really efficient solution without knowing the name of the database engine, I googled cde3 database I found nothing. The solutions presented have time complexity O(n x m) where n is the number of records and m is the total of characters to be searched as a solution using natively Inverted index has time complexity O(log n).

  • Ahhh, I thought you were asking the name of my database.

2 answers

4

In addition, use the option Upper/Lower for best use.

SELECT * FROM usuarios WHERE upper(nome) LIKE upper('%Silva%').

So you guarantee that the result will be 'Silva', no matter how you write it (SiLvA, sILvA, etc.).

3


To return all the people who have Silva anywhere in the text, use the operator LIKE.

SELECT * FROM usuarios WHERE nome LIKE '%Silva%'

Stay tuned for the performance cost of this operation.

  • I agree the LIKE operator can consume a lot in a query depending on the size of the entity to which the search is made.

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