Should I create an Index for a large insert operation in mysql? -

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lets have following table 8 billion columns: subject text, predicate text, object text , want create table count different text values this:

create table nodes (id bigint unsigned primary key auto increment, val text,     count bigint unsigned); insert nodes(val,count) select subject, count(*) count triples group subject

would index on subject predicate , object increase or decrease speed of insertion?

a general rule of thumb: indices typically decrease write speeds, while increasing read speeds.


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