Seaquel
SQL Server error code

SQL Server error 8623

SQL Server raises error 8623 at severity 16, which marks a problem with the query or data that you can correct.

The query processor ran out of internal resources and could not produce a query plan. This is a rare event and only expected for extremely complex queries or queries that reference a very large number of tables or partitions. Please simplify the query. If you believe you have received this message in error, contact Customer Support Services for more information.
Msg8623
NameOPTIMIZER_NOPLAN_ERR
Severity16
Group8000–8999

What it means

The Query Optimizer is unable to generate a query plan due to either running out of resources or the query being too complex, two different states can be returned for this error

Source: Database Engine events and errors