Sqlite: store payloads/attributes in separate table

[cschleiden]

This change adds a new attributes table to the sqlite backend. Serialized attributes for events are stored in that table instead of inline.

Contributes to: #39

[cschleiden]

!bench !large

[cschleiden]

!bench !large

[cschleiden]

!bench

[cschleiden]

!bench !large

[github-actions]

Default run

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
mysql-main	834.5 ± 74.6	723.6	975.9	1.00
mysql-pr	868.6 ± 173.3	608.0	1050.8	1.04 ± 0.23

Command	Mean [s]	Min [s]	Max [s]	Relative
sqlite-main	1.057 ± 0.209	0.705	1.309	1.01 ± 0.28
sqlite-pr	1.050 ± 0.207	0.689	1.293	1.00

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
redis-main	268.4 ± 41.6	213.0	371.1	1.08 ± 0.20
redis-pr	249.3 ± 25.4	207.0	278.4	1.00

[github-actions]

Default run

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
mysql-main	383.0 ± 64.6	306.1	483.5	1.05 ± 0.22
mysql-pr	363.8 ± 45.7	303.0	476.2	1.00

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
sqlite-main	569.4 ± 99.0	444.2	778.2	1.00
sqlite-pr	570.4 ± 110.4	430.5	816.9	1.00 ± 0.26

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
redis-main	128.4 ± 15.4	88.9	173.1	1.00
redis-pr	142.5 ± 20.2	123.5	204.6	1.11 ± 0.21

Large payload run (1MB)

Command	Mean [s]	Min [s]	Max [s]	Relative
sqlite-main	23.847 ± 0.744	22.488	24.933	1.08 ± 0.05
sqlite-pr	22.127 ± 0.784	20.825	23.013	1.00

Command	Mean [s]	Min [s]	Max [s]	Relative
redis-main	22.753 ± 0.770	21.416	23.913	1.00 ± 0.04
redis-pr	22.746 ± 0.522	21.869	23.407	1.00