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Be careful deleting a parameter, it will change the name of the Outer Name of the parameter below it.
This is more attention to detail that anything else. If you are in a hurry and fail to notice this, your dependent queries will fail and you might not notice right away what went wrong. There is no checking of any kind on the parameter box to see if inner and outer names match up.
Parameters names in xactions must match names of parameters in PRPT files.
If you have a parameter in your report called 'date_init', you'll need to have a matching parameter also named date_init in your xaction. It is not enough to match the data type and position/order of the parameter being passed in (ie, passed first, second or third.) Fortunately this error will slap you right away if you do it. Just go into xaction writing knowing this is a rule you have to follow. It is probably good practice as well.
A working example of passing a date date type from an xaction to a PRPT file
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