Today, the operator reported that there is a data in the backend that cannot be modified. I checked the error for a long time, and finally found that the value of the url field of this data is greater than the varchar (100) I defined. It is very simple to solve the problem. Just change it. But I would like to ask you how did this data come from?
you can take a look at this article Portal
length () and char_length () there is still a difference. I don't know how you calculate the length of url field values. Varchar refers to fields that can be inserted into char_length=100, while length may be more than that, if it contains Chinese characters.
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$selectTip = $pdo->query("SELECT * FROM `tips_rate` WHERE `tip_id` = ".$row[ id ]." " ); $selecttotal = mysqli_num_rows($selectTip); $rate = $pdo->query("SELEC...
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like this SELECT * FROM material WHERE {key:value} limit 1 ...
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Table structure ...
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