The first aggregation using VCI immediately after an instance is started may take time, because the VCI data has not been loaded to buffer.

Therefore, use the preload feature to load the VCI data to buffer in advance when performing VCI aggregation after an instance is started.

When using the preload feature, execute the function pgx_prewarm_vci to each VCI created with CREATE INDEX.

db01=# SELECT pgx_prewarm_vci('idx_vci');