Tracing Cassandra queries
Cassandra allows us to trace a query session; this can be used to debug queries that perform badly. On the cqlsh
prompt, you can enable tracing using the command TRACING ON
. After that, each query run on the prompt will be traced, and the trace output will be displayed.
Cassandra automatically saves a traced session in the system_traces
keyspace. A saved session can be referenced later on for up to 24 hours.
Take the example of tracing an INSERT
statement. Let's first create a column family with replication factor 1
, as shown in the following example. We're taking a low replication factor for the simplicity of the example. In our example, 10.78.171.11
is the coordinator node and 10.78.171.12
is the replica node:
cqlsh> ...
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