Comparing Eq, Contains And Other Operators For Caml Queries In Sharepoint

What is CAML and Why Use Query Operators?

Collaborative Application Markup Language (CAML) is an XML-based querying language used in Microsoft SharePoint to define queries against list data. CAML provides a wide range of operators that allow performing powerful lookups, filtering, and shaping of SharePoint list content.

Some common CAML query operators include:

• Eq – Matches values that are equal to the specified value
• Contains – Matches values that contain the specified text
• BeginsWith – Matches values starting with the specified text

Using CAML query operators rather than other search methods in SharePoint has several key benefits:

• Precision – Operators like Eq allow exact matches instead of fuzzy searches
• Efficiency – Queries execute directly against the SharePoint database for fast results
• Flexibility – Complex conditional logic can be created with And, Or operators
• Native Integration – CAML is deeply interwoven into SharePoint allowing optimization

Key Differences Between the Eq and Contains Operators

The Eq and Contains operators are two of the most frequently used operators for querying SharePoint lists. However, they work differently:

• Eq performs an exact match on the field value specified in the query. For example, Eq “ProjectA” would return only items where the field’s value is exactly “ProjectA”.
• Contains does a substring match returning items where the field’s value contains the text specified anywhere inside it. Contains “ProjectA” would return “ProjectA”, “XYZProjectABC”, etc.

To see this in action, here is an example CAML query with both Eq and Contains:

<Query>
  <Where> 
    <Eq>
      <FieldRef Name="Project"/> 
      <Value Type="Text">ProjectA</Value>
    </Eq>
    <Contains>   
      <FieldRef Name="Project"/>
      <Value Type="Text">ProjectA</Value>
    </Contains>
  </Where>
</Query>  

This query would return all items where:

1. The Project field matches “ProjectA” exactly using Eq
2. The Project field contains “ProjectA” using the Contains operator

Other Useful Comparison Operators

In addition to Eq and Contains, CAML also offers other useful operators:

BeginsWith Operator

The BeginsWith operator matches values starting with the specified text. For example:

  
<BeginsWith>
  <FieldRef Name="Project"/>
  <Value Type="Text">Project</Value> 
</BeginsWith>

This would match values like “ProjectApple” and “ProjectBeta” but not “AppProjectX”. Useful for partial matches.

In Operator

The In operator allows matching multiple values at once unlike Eq. For example:

<In>
  <FieldRef Name="Status"/> 
  <Values>
    <Value Type="Text">Active</Value>  
    <Value Type="Text">Pending</Value>
  </Values>
</In> 

This query would return items where the Status equals “Active” or “Pending”. Simplifies having multiple Or conditions.

Real-World Examples of CAML Operator Usage

Some common real-world examples of using CAML query operators include:

Finding Documents by Keywords

<Contains>
  <FieldRef Name="DocumentContent"/> 
  <Value Type="Text">SharePoint</Value> 
</Contains>

This query would return all documents containing the word “SharePoint” anywhere in the content. Useful for basic keyword searches.

Getting Items Created This Month

<And>
  <Geq> 
    <FieldRef Name="Created"/>
    <Value Type="DateTime">2023-02-01</Value>
  </Geq>
  <Lt>
    <FieldRef Name="Created"/> 
    <Value Type="DateTime">2023-03-01</Value>
  </Lt> 
</And>

This query uses the Greater Than Or Equal To (Geq) and Less Than (Lt) operators to return items created in February 2023.

Getting Items Matching Categories

 
<In>
  <FieldRef Name="Category"/>
  <Values>  
    <Value Type="Text">Finance</Value>
    <Value Type="Text">Reporting</Value>
  </Values> 
</In>

This query returns list items categorized as either “Finance” or “Reporting” demonstrating the In operator.

Recommendations for Effective CAML Queries

Some best practices for working with CAML queries include:

• Use indexed columns like ID for faster lookups
• Avoid operators that cause full table scans like Contains
• Retrieve only the fields you need not the whole item
• Watch for performance issues with very large lists
• Test complex queries to ensure correct logic
• Integrate with SharePoint Search when possible

Properly structuring CAML queries and choosing the right operators for your specific filtering scenario can take some trial and error. But used correctly, CAML empowers you to slice and dice SharePoint list data efficiently.