Don't insert entry if already exist

Question

How to not insert the values if same question_text exist but not for the first_word.

Example (The question_text is the whole sentence and the first word is the first word in the sentence.)

He is crazy. //insert

He is smart. //insert

He is smart. //exist don't insert

$first_word = current(explode(' ', $_POST['question_text']));

mysql_query("INSERT INTO questions (question_id,question_text,field_name)
             VALUES ('','$_POST[question_text]','$first_word')");

You don't want two entries with the same value? – powtac Mar 24 '11 at 15:09 — powtac, Mar 24 '11 at 15:09
Yes i don't want the same value to be inserted. – Abby Mar 24 '11 at 15:13 — Abby, Mar 24 '11 at 15:13
Can you not have question_text set as unique? – Andre Backlund Mar 24 '11 at 15:13 — Andre Backlund, Mar 24 '11 at 15:13

score 3 · Answer 1 · answered Mar 24 '11 at 15:13

3

You could run this SQL once query to prevent double entries with the same content:

ALTER TABLE questions ADD UNIQUE(question_text);

answered Mar 24 '11 at 15:13

powtac

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score 0 · Answer 2 · edited May 23 '17 at 12:11

0

You can't do that with this query. You need to write another query first to check for the existence of the row you don't want to duplicate.

Also, the code is vulnerable to SQL injection attacks. See here for information on how to fix that: Protect against SQL injection

edited May 23 '17 at 12:11

Community

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answered Mar 24 '11 at 15:09

Jon

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score 0 · Answer 3 · answered Mar 24 '11 at 15:14

0

MySQL has the INSERT ON DUPLICATE KEY UPDATE statement, which you could use. But in the example you posted it would probably not be a good way to do it.

answered Mar 24 '11 at 15:14

JRL

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Don't insert entry if already exist

3 Answers3