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Let's explain the scenario further, denormalized table(or the commonly known 'wide table') model is a common data modeling method, which connects multiple tables to form a unified wide table to improve query and analysis efficiency.
The data of wide denormalized table comes from different source tables. When writing or updating data, it usually adopts the mode of specifying the column list to write.

For example, there is a wide denormalized table t1 which has a primary key `a`:

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where column b, c, d from s1 table, column e, f, g from s2 table,
by different processing data from the source table s1 and s2,  the two insertions specify a different column list written to the wide denormalized table, ideally the two insertions will not affect each others' column

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