Element fails to start as elementdata has >200k rows

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I have an element that is failing to start, due to the Cassndra elementdata having 200983 rows in the sldmadb_elementdata.elementdata table.

I've verified this is not the gc_grace_seconds/tombstone issue. currently zero tombstones are reported.

Other elements are starting and stoppping normally.

What can I do to make this element start?

In the element log I get

2026/06/19 11:21:08.275|SLProtocol - 27676 - DM-ARM-01|20364|CProtocol::LoadElementDataAllPIDs|CRU|-1|Querying elementdata
2026/06/19 11:21:22.262|SLProtocol - 27676 - DM-ARM-01|20364|ElementDataPagedQuerier::Query|ERR|-1|Could not start reading the element data for 400157/24: 0x80131500: 
2026/06/19 11:21:22.263|SLProtocol - 27676 - DM-ARM-01|20364|CProtocol::InitializeParameters|ERR|0|Failed to query elementdata for 400157/24: General database failure.
2026/06/19 11:21:22.264|SLProtocol - 27676 - DM-ARM-01|20364|CProtocol::Init|ERR|0|InitializeParameters failed General database failure. (hr = 0x80040226)
2026/06/19 11:21:22.264|SLDataMiner.exe - DM-ARM-01|32112|CElement::Start|ERR|-1|InitializeProtocol for Element DM-ARM-01 failed with General database failure.. (hr = 0x80040226)
2026/06/19 11:21:22.265|SLDataMiner.exe - DM-ARM-01|32112|CElement::Activate|ERR|-1|Start failed. General database failure. (hr = 0x80040226)
2026/06/19 11:21:22.265|SLDataMiner.exe - DM-ARM-01|32112|CElement::SetState|DBG|0|** Setting state from 1 to 10 (RealState = 4)

Running this cql query, it either times out, or returns 200983
SELECT COUNT(*) FROM sldmadb_elementdata.elementdata WHERE d = 400157 AND e = 24;
Chris Glover [DevOps Advocate] Answered question

1 Answer

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We found by doing a bit of scary work in Cassandra, we were able to delete the offending element tables, restart the element, and then reimported the data.

The problem comes as each table cell has it's own row in the database, so a router sources table, with approx 4000 sources in it, results in 44000 rows in the Cassandra database, then again for the destinations. So, it's quite easy to see how that ballooons to a very large number of rows.

I'm not going to give the CQL commands here, as one false move will lead to a very bad day!

What I will say is sldmadb_elementdata.elementdata has columns d, e and p. d = dma id, e = element number and p = parameter

Chris Glover [DevOps Advocate] Answered question