estimate_data_size()

Applies to: ✅ Azure Data Explorer ✅ Azure Monitor ✅ Microsoft Sentinel

Returns an estimated data size in bytes of the selected columns of the tabular expression.

estimate_data_size(columns)

Learn more about syntax conventions.

The estimated data size in bytes of the referenced columns. Estimation is based on data types and actual values. For example, the data size for the string '{"a":"bcd"}' is smaller than the dynamic value dynamic({"a":"bcd"}) because the latter's internal representation is more complex than that of a string.

The following example calculates the total data size using estimate_data_size().

range x from 1 to 10 step 1                    // x (long) is 8 
| extend Text = '1234567890'                   // Text length is 10  
| summarize Total=sum(estimate_data_size(*))   // (8+10)x10 = 180

Output

• Estimate table size