denisvenis, CONTINUEIF indicates that you want to concatenate a row of data in the input file with the next row and treat it as 'one' row of data being loaded.
You can concatenate any number of rows up to a maximum size of 32,767.
The CONTINUEIF parameter has nothing to do with '...removes data from the table space and replaces just the data for the first table in multitable tablespace.'
Load Replace is what does this. One of the first things a Load Replace does is to remove all rows from a Table Space. Note that it is the Table Space and not just the Table that has all rows removed.
If you have two (or more) Tables in a Table Space and you run:
LOAD DATA REPLACE INTO TABLE1
LOAD DATA REPLACE INTO TABLE2
You would end up with only data in Table2. The First load removes all rows from the Table Space (both tables) and then add data to Table1. The Second load removes all rows from the Table Space (both tables although Table2 was already empty at this point) and then adds rows to Table2.
Just for completeness, if you want to remove all rows from both tables and then load both tables, you need to use Replace and Resume Yes.
LOAD DATA REPLACE INTO TABLE1
LOAD DATA RESUME YES INTO TABLE2.