sql - Update or Insert value if a field is NULL -


i know simple question wanted sure. have null value in field, , want change null value. change null value use insert or update? 

for example: insert datatable (column 1) values (1) 'column 1' = null

or 

update datatable  set 'column 1' = 1 'column 1' = null

thank you.

you use update updates , insert inserts(new records). update incorrect since cannot compare null values = or <>. therefore have use is:

update datatable  set [column 1] = 1 [column 1] null

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