python - Updating SQL Table Where Fields May be Null -

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i have sql table want update daily. data records need updated pulled web, text file. have python script read data, , figure out records need updated.

given potentially large number of records updated each day, following:

with get_connection_to('database') connection:      cursor = connection.cursor()      cursor.executemany(query, data)

the problem approach of fields may potenitall null\ none

so if use query like

update tablename set active = 0 field1 = ?     , field2 = ?     , field3 = ?     , field4 = ?     , field5 = ?

then records contain null value won't updated.

the best idea i've come far loop on each row, inspect each element, construct sql query each update, , perform each transaction separately. feels inelegant, , slow solution problem.

has got better solution?

update tablename set active = 0 nullif(?,field1) null   , nullif(?,field2) null   , nullif(?,field3) null   , nullif(?,field4) null   , nullif(?,field5) null

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