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Query anti-patterns

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Composing optimized queries for Dataverse is vital to ensure applications provide a fast, responsive, and reliable experience. Learn about patterns to avoid when composing queries for standard tables using the RetrieveMultiple message, or messages that have a parameter that inherits from the QueryBase class. This guidance also applies when sending a GET request against a collection of records using OData.

Note

The guidance here might not apply for Elastic tables or when using Dataverse Search.

Minimize the number of selected columns

Don't include columns you don't need in your query. Queries that return all columns or include a large number of columns can encounter performance issues due to the size of the dataset or complexity of the query.

Minimize the number of selected logical columns

You should avoid requesting too many columns, especially logical columns. A logical column contains values that are stored in different database tables. The AttributeMetadata.IsLogical property tells you whether a column is a logical column. Queries that contain many logical columns are slower because Dataverse needs to combine the data from other database tables.

Avoid leading wild cards in filter conditions

Queries that use conditions with leading wild cards (either explicitly, or implicitly with an operator like ends-with) can lead to bad performance. Dataverse can't take advantage of database indexes when a query using leading wild cards, which forces SQL to scan the entire table. Table scans can happen even if there are other nonleading wild card queries that limit the result set.

The following example is a FetchXml condition element that uses a leading wild card:

<condition attribute='accountnumber'
   operator='like'
   value='%234' />

When queries time out and this pattern is detected, Dataverse returns a unique error to help identify which queries are using this pattern:

Name: LeadingWildcardCauseTimeout
Code: 0x80048573
Number: -2147187341
Message: The database operation timed out; this may be due to a leading wildcard value being used in a filter condition. Please consider removing filter conditions on leading wildcard values, as these filter conditions are expensive and may cause timeouts.

Dataverse heavily throttles leading wild card queries that are identified as a risk to the health of the environment to help prevent outages. When a query fails due to throttling and this pattern is detected, Dataverse returns a unique error:

Name: DataEngineLeadingWildcardQueryThrottling
Code: 0x80048644
Number: -2147187132
Message: This query cannot be executed because it conflicts with Query Throttling; the query uses a leading wildcard value in a filter condition, which will cause the query to be throttled more aggressively.

If you find yourself using leading wild card queries, look into these options:

  • Use Dataverse search instead.
  • Change your data model to help people avoid needing leading wild cards.

Other wildcard characters

As described in Use wildcard characters in conditions for string values, other characters beyond the percent sign ('%') character can act like a wildcard. Following are two example query strings that also behave like leading wildcards:

  • _234%
  • [^a]234%

Dataverse heavily throttles queries with search strings that start with these other leading wildcard special characters.

Hyphen character

Database collation unicode sorting rules make some search strings that start with a hyphen ('-') perform like leading wildcard searches. Search strings that start with a hyphen can't take advantage of database indexes if the search string doesn't contain a nonwildcard character before the occurrence of the '%' character in the string. For example, -% and -%234 can't efficiently use database indexes, while -234% can. Dataverse heavily throttles inefficient search strings that start with hyphens. To understand more about the database collation unicode sorting rules for hyphens, see SQL Server collations.

Avoid using formula or calculated columns in filter conditions

Formula and calculated column values are calculated in real-time when they're retrieved. Queries that use filters on these columns force Dataverse to calculate the value for each possible record that can be returned so the filter can be applied. Queries are slower because Dataverse can't improve the performance of these queries using SQL.

When queries time out and this pattern is detected, Dataverse returns a unique error to help identify which queries are using this pattern:

Name: ComputedColumnCauseTimeout
Code: 0x80048574
Number: -2147187340
Message: The database operation timed out; this may be due to a computed column being used in a filter condition. Please consider removing filter conditions on computed columns, as these filter conditions are expensive and may cause timeouts.

Dataverse heavily throttles queries that have filters on calculated columns that are identified as a risk to the health of the environment to help prevent outages. When a query fails due to throttling and this pattern is detected, Dataverse returns a unique error:

Name: DataEngineComputedColumnQueryThrottling
Code: 0x80048744
Number: -2147186876
Message: This query cannot be executed because it conflicts with Query Throttling; the query uses a computed column in a filter condition, which will cause the query to be throttled more aggressively.

Avoid ordering by choice columns

When you use FetchXml or QueryExpression, when you order query results using a choice column, the results are sorted using the localized label for each choice option. Ordering by the number value stored in the database wouldn't provide a good experience in your application. You should know that ordering on choice columns requires more compute resources to join and sort the rows by the localized label value. This extra work makes the query slower. If possible, try to avoid ordering results by choice column values.

Note

OData is different. With the Dataverse Web API, $orderby sorts rows using the integer value of the choice column rather than the localized label.

Avoid ordering by columns in related tables

Ordering by columns on related tables makes the query slower because of the added complexity.

Ordering by related tables should only be done when needed to as described here:

Avoid using conditions on large text columns

Dataverse has two types of columns that can store large strings of text:

The limit for both of these columns is specified using the MaxLength property.

You can use conditions on string columns that have a MaxLength configured for fewer than 850 characters.

All memo columns or string columns with a MaxLength greater than 850 are defined in Dataverse as large text columns. Large text columns are too large to effectively index, which leads to bad performance when included in a filter condition.

Dataverse search is a better choice to query data in these kinds of columns.

Dataverse error for query time outs caused by anti-patterns

When a query times out and the query is using one of the anti-patterns detailed on this page, Dataverse returns the following unique error to help identify which anti-patterns the query is using:

Name: PerformanceValidationIssuesCauseTimeout
Code: 0x80048575
Number: -2147187339
Message: The database operation timed out; this may be due to the query performance issues identified in a query executed on this request. Please optimize the query by addressing the following identified performance issues: {0}. Please reference this document for guidance: https://go.microsoft.com/fwlink/?linkid=2300520

The {0} part of the exception message lists the anti-pattern that the query is using. If there are multiple anti-patterns used by the query, they're comma separated. For example, if a query is filtering on a large text column and is also selecting a large number of columns, the exception message contains the string PerformanceLargeColumnSearch,LargeAmountOfAttributes. The following table lists the anti-patterns with links to explanations:

Anti-pattern identifier Explanation link
PerformanceLeadingWildCard Avoid leading wild cards in filter conditions
PerformanceLargeColumnSearch Avoid using conditions on large text columns
OrderOnEnumAttribute Avoid ordering by choice columns
OrderOnPropertiesFromJoinedTables Avoid ordering by columns in related tables
LargeAmountOfAttributes Minimize the number of selected columns
LargeAmountOfLogicalAttributes Minimize the number of selected logical columns
FilteringOnCalculatedColumns Avoid using formula or calculated columns in filter conditions

Use the guidance on this page to understand the anti-patterns and modify the query to avoid usage of these anti-patterns.

Note

If a query contains either the PerformanceLeadingWildCard or the FilteringOnCalculatedColumns anti-pattern, a different Dataverse error is thrown. Queries that use the PerformanceLeadingWildCard anti-pattern throw the LeadingWildcardCauseTimeout error mentioned on this page, and queries that use the FilteringOnCalculatedColumns anti-pattern throw the ComputedColumnCauseTimeout error mentioned on this page.

The LeadingWildcardCauseTimeout and ComputedColumnCauseTimeout errors predate the PerformanceValidationIssuesCauseTimeout error; LeadingWildcardCauseTimeout and ComputedColumnCauseTimeout continue to be thrown to maintain backward compatibility.

Query throttling
Use wildcard characters in conditions for string values
Query data using FetchXml
Query data using QueryExpression
Use OData to query data