how many characters should i limit a thread body to?

im using doctrine and need to specify the length of a thread body (datatype开发者_如何学JAVA: blob).

i wonder how many characters i should limit the user to type for a thread body?

what is normal?

thanks!

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The BLOB datatype is simply a binary large object, I am not sure if your question relates to the size or length of what they should type, or should be able to type.