SQL Server Interview: As a DBA, which wait types are important to check

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In the SQL Server DBA Interview, questions related to wait types are prevalent. In this post, I am sharing a small note on few important wait types those you guys can use in your replies.

You can use below query to check the different waits in SQL Server

Important wait types:

ASYNC_NETWORK_IO: Network related waits, which causes by a client application that is not processing results from the SQL Server

LCK_M_IX: Occurs when a thread is waiting for a table or page IX lock so that a record insert or update can happen

LCK_M_X: Occurs when issue of lock escalation happens

CXPACKET: Issue in Parallel query execution, indicates that SPID is waiting for parallel processing

PAGEIOLATCH_SH: Occurs when data page is waiting to be read into memory

OLEDB: When SPID is waiting for remote procedure calls from OLEDB linked server

SOS_SCHEDULER_YIELD: When high CPU usage occurs

WRITELOG: Waiting to write the contents of the log cache to disk