Podcast #128: We chat with Kent C Dodds about why he loves React and discuss what life was like in the dark days before Git. Listen now.
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A database concept used to represent missing, unknown or inapplicable data.

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I have a table like the following: create table my_table ( id int8 not null, id_A int8 not null, id_B int8 not null, id_C int8 null, constraint pk_my_table primary key (id … VALUES (1, 1, 2, NULL); INSERT INTO my_table VALUES (2, 1, 2, NULL); But it doesn't behave as expected because according to the documentation, two NULL values are not compared to each other, so both …
asked Dec 27 '11 by Manuel Leduc