An example of mysql string escape function
This article mainly introduces "mysql string escape function examples". In daily operation, I believe many people have doubts about mysql string escape function examples. The editor consulted all kinds of materials and sorted out simple and easy-to-use operation methods. I hope it will be helpful for you to answer the doubts of "mysql string escape function examples". Next, please follow the editor to study!
Inserting a data table in mysql will cause syntax errors if there is a'\ "in the data. There is no need to explain this, you know, so you need to write an escape function. At first, you want to use string's replace directly, but this method needs to be called three times.
It feels inefficient to put it on the server, so I write one in C, which feels OK. The time complexity has nothing to do with the number of escape characters that need to be escaped. If the source string does not match, there is no need for copy operation.
/ / escape function, 'convert to\'
Bool ConverToDBStr (const char* src,char*dst)
{
Int I =-1 ram / record the location of the last match
Int dOffset = 0 position hand / target string cursor
Int nCopy = 0 copy / the number of bytes that need to be copy this time
Const char*p = src
While (* p)
{
If (* paired bands'\\'| | * paired frames'\'| | * paired fragments'"'")
{
NCopy = p-src-i-1
Memcpy (dst+dOffset,src+i+1,nCopy)
DOffset+=nCopy
* (dst+Offset) ='\\'
* (dst+dOffset+1) = * p
DOffset+=2
I = p-src
}
Pendant +
}
If (dOffset > 0) / / matches the last string of copy
{
Memcpy (dst+dOffset,src+i+1,p-src-i)
Return true
}
Return false
}
As you can see, replace can be implemented with a slight change to this function.
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