Reload vs Partial Reload

Suppose we've got a table like this:

Office:

LOAD * INLINE [

    EmployeeID, Name

    1, 100

    2, 200

    3, 300

    4, 400

    5, 500

    6, 600

];

Field EmployeeID looks like
Change a bit the script

Office:

LOAD * INLINE [

    EmployeeID, Name

    1, 100

    2, 200

    3, 300

    4, 400

    5, 500

    6, 600

];  



Office:

LOAD * INLINE [

 EmployeeID, Name

 6, 600

 7, 700

];

run again it (Ctrl+R) and take a look at EmployeeID field

we may see new seventh employee
But if we change a bit properties of EmployeeID field (Show Frequency)

we will see that the sixth employee presented twice

To avoid duplicating we need to check EmployeeID field like this:

Office:

LOAD * INLINE [

    EmployeeID, Name

    1, 100

    2, 200

    3, 300

    4, 400

    5, 500

    6, 600

];  



Office:

LOAD * INLINE [

 EmployeeID, Name

 6, 600

 7, 700

]

Where not Exists(EmployeeID);

It's a key moment.

Now change a script like this (ADD ONLY)

Office:

LOAD * INLINE [

    EmployeeID, Name

    1, 100

    2, 200

    3, 300

    4, 400

    5, 500

    6, 600

];  



Office:

ADD ONLY LOAD * INLINE [

 EmployeeID, Name

 6, 600

 7, 700

]



Where not Exists(EmployeeID);

and Run it(Ctrl+R). We see 

but if we Run Partial (Ctrl+Shift+R) we see 

At the and let's come back to previous script without ADD ONLY and Exists keywords

Office:

LOAD * INLINE [

    EmployeeID, Name

    1, 100

    2, 200

    3, 300

    4, 400

    5, 500

    6, 600

];  



Office:

ADD LOAD * INLINE [

 EmployeeID, Name

 6, 600

 7, 700

];

//Where not Exists(EmployeeID);

Every time we  Run Partial (Ctrl+Shift+R) we see that duplicates grow again

and again

Copyright © 2015 Ruslan Goncharov