KB4548597 - Cumulative Update 4 for SQL Server 2019

Applies to: SQL Server 2019 on LinuxSQL Server 2019 on Windows

This article describes Cumulative Update package 4 (CU4) for SQL Server 2019. This update contains fixes that were released after the initial release of SQL Server 2019 and updates the SQL Server and Analysis services components to the following builds.

Component Product version File version
SQL Server 15.0.4033.1 2019.150.4033.1
Analysis Services 2018.150.34.14


Important notices

This article also provides important information about the following situations:

Cumulative updates (CU)

  • Each new CU contains all the fixes that were included with the previous CU for the installed version of SQL Server.
  • SQL Server CUs are certified to the same levels as Service Packs, and should be installed at the same level of confidence.
  • Microsoft recommends ongoing, proactive installation of CUs as they become available according to these guidelines:
    • Historical data shows that a significant number of support cases involve an issue that has already been addressed in a released CU.
    • CUs may contain added value over and above hotfixes. This includes supportability, manageability, and reliability updates.
  • We recommend that you test SQL Server CUs before deploying to production environments.

How to obtain this cumulative update package for SQL Server 2019 on Windows

The following update is available from the Microsoft Download Center:

Download icon
Microsoft Download Center: Download the latest cumulative update package for SQL Server 2019 now. 

  • Note Microsoft Download Center will always present the latest SQL Server 2019 CU release.
  • If the download page does not appear, contact Microsoft Customer Service and Support to obtain the cumulative update package.

Download icon
Microsoft Update Catalog: Download cumulative update packages for SQL Server 2019

  • Note Microsoft Update Catalog contains this SQL Server 2019 CU and previously released SQL Server 2019 CU releases.
  • This CU is also available through Windows Server Update Services (WSUS).
  • We recommend that you always install the latest cumulative update that is available.

How to obtain this cumulative update package for SQL Server 2019 on Linux

To update SQL Server 2019 on Linux to the latest CU, you must first have the Cumulative Update repository configured. Then, update your SQL Server packages by using the appropriate platform-specific update command.

For installation instructions and direct links to the CU package downloads, see the SQL Server 2019 Release Notes.

How to obtain this cumulative update package for SQL Server 2019 Big Data Clusters (BDC)

To implement SQL Server 2019 BDC on Linux to the latest CU, see the Big Data Clusters Deployment Guidance.

Starting in SQL Server 2019 CU1, you can perform in-place upgrades for Big Data Clusters from the production supported releases (SQL Server 2019 GDR1). For more information, see How to upgrade SQL Server Big Data Clusters.

For additional information, see the Big Data Clusters release notes.

List of improvements and fixes included in this Cumulative Update

For more information about the bugs that are fixed and enhancements that are included in this cumulative update, see the following Microsoft Knowledge Base articles.

Bug Reference KB article number Description Fix area Platform
13443390   Adds new SERVERPROPERTY "IsBigDataCluster" to retrieve a boolean value that describes whether the instance is BDC or not.  Big Data Cluster (BDC)  All
13441894 4538581 FIX: Scalar UDF Inlining issues in SQL Server 2019 SQL Engine All
13411047 4552159 FIX: Error occurs when you apply a security policy on PolyBase external table in SQL Server 2019 SQL Engine All
13402700 4552205 FIX: Error occurs when you try to create external table in PolyBase with database_default as collation in SQL Server 2019 SQL Engine All
13414966 4538688 FIX: Severe spinlock contention occurs in SQL Server 2019 SQL Engine All
13445859   Access violation error occurs when you cancel queries against Big Data Cluster (BDC) storage pool or any OPENROWSET query on an instance of SQL Server 2019. SQL Engine All
13407609 4538268 FIX: "Expired BLOB handle" error occurs when cross-database transaction involves communication with MSDTC in SQL Server 2017 and 2019 SQL performance All
13421861 4541096 FIX: Access Violation occurs when you run query on computed columns in SQL Server SQL performance All
13421852 4543027 FIX: Parallel sampled filtered statistics may cause incorrect histogram scaling in SQL Server 2016 and 2019 SQL performance All
13440147   Starting from Cumulative Update 4 (CU4) for SQL Server 2019, when auditing DMVs and DBCC commands to get query optimization statistics and if sensitive data is revealed,  the 'data_sensitivity_information' column of the audit record will be populated. SQL security All
13429199   Improved error message is returned when you try to link the base and history tables on which data classification is already defined. SQL security All
13402561 4532432 Mssql-conf tool fails if IPV6 is disabled on the Linux system SQL Engine Linux
13357335   Assume that the Format String Expression property of a Calculation Item from a Calculation Group is set. The performance degradation occurs when you run MDX queries generated by MDX based client tools and may also occur when MDX queries do not refer to the calculation item with Format String Expression set. However, the performance degradation is not so evident on equivalent DAX queries generated by Power BI Desktop visuals. Analysis Services Windows
13421880 4541300 FIX: Fix incorrect values in auto seeding XEvents in SQL Server High Availability Windows
13421858 4541303 FIX: Non-yielding Scheduler error may occur with Always On availability group in Microsoft SQL Server High Availability Windows
13421856 4541309 FIX: Missing log block may occur when you use Always On availability group in SQL Server High Availability Windows
13421865 4541724 FIX: Intermittent non-yielding scheduler occurs when memory-optimized database running under heavy I/O activities in SQL Server 2016 and 2019 In-Memory OLTP Windows
13417390   In the Service Accounts interface of SQL Server Setup, password validation may fail if only username is entered before the correct password is entered. This failed validation may lock out the domain service account if you do this repeatedly and domain policy set to lock accounts after few unsuccessful attempts. Setup & Install Windows
13407610 4538365 FIX: Change Tracking cleanup does not work when invalid cleanup and hardened cleanup version are negative in SQL Server 2017 and 2019 SQL Engine Windows
13421889 4539815 FIX: Access violation occurs when change tracking auto cleanup tries to clean up side tables in SQL Server SQL Engine Windows
13421887 4540107 FIX: System or background task may fail when number of sessions reaches the maximum limit in SQL Server 2016 and 2019 SQL Engine Windows
13443768 4540121 FIX: sp_execute_external_script doesn't run when you install SQL Server 2019 with Machine Learning Services and a customized Shared feature directory SQL Engine Windows
13421916 4540342 FIX: Non-yielding scheduler condition occurs with CONNECTION_MANAGER spinlock in SQL Server SQL Engine Windows
13421902 4540903 FIX: Non-yielding scheduler dump occurs in InterlockedCompareExchangePointer and SOS_RWLock in SQL Server 2016 and 2019 SQL Engine Windows
13421876 4541435 FIX: Error occurs when you rename a column on temporal current table in SQL Server SQL Engine Windows
13421863 4541520 FIX: Assertion occurs when you process a malformed XML message sent as message in Service Broker queue in SQL Server SQL Engine Windows
13421900 4541762 FIX: Management Data Warehouse Server Activity Collection Set may fail in SQL Server 2016 and 2019 SQL Engine Windows
13421882 4541770 FIX: Assertion failure occurs when persistent log buffer is used in SQL Server 2016 and 2019 SQL Engine Windows
13404458 4548103 FIX: Performance degradation occurs on PMEM devices with Hybrid Buffer Pool enabled in SQL Server 2019 SQL Engine Windows
13376878   When an application performs bulk copy operations and a subsequent select in the same transaction against a database with simple or bulk-logged recovery model, SQL Server Access Violations may occur and repeat until the service is restarted. SQL Engine Windows
13418869   SQL Writer will add its version and log tracing parameters to the log header when the service starts. SQL Engine Windows
13431504   Improves SQL Writer for better handling of COPY_ONLY backup messages in SQL Server 2019. SQL Engine Windows
13407603 4538497 FIX: Slow query performance when using query predicates with UPPER, LOWER or RTRIM with default CE in SQL Server 2017 and 2019 SQL performance Windows
13421869 4539880 FIX: Access violation occurs with wait_info XEvent on busy SQL Server SQL performance Windows
13421907 4540346 FIX: MERGE statement fails with assert “Attempt to access expired blob handle (1)” in SQL Server 2016 and 2019 SQL performance Windows
13421911 4540901 FIX: SQL Server may terminate due to lock conflicts during error message processing in SQL Server 2016 and 2019 SQL security Windows

Notes for this update

Known Issue

Under certain circumstances, there is a known uninstall issue with this SQL Server 2019 CU4. If you uninstall this CU, SQL server doesn’t come online and you find the following SQL Server error log message:

Mitigation is to enable Trace Flag -T902, then SQL server will come online and you are done. You don’t need to uninstall it again. To upgrade to new CU you need to remove this flag first.

SQL Server 2019 CU5 or any later CU release contains the fix.

Hybrid environments deployment

When you deploy an update to a hybrid environment (such as AlwaysOn, replication, cluster, and mirroring), we recommend that you refer to the following articles before you deploy the update:


To apply this cumulative update package, you must be running SQL Server 2019.

Restart information

You may have to restart the computer after you apply this cumulative update package.

Registry information

To use one of the hotfixes in this package, you do not have to make any changes to the registry.