LEFT - Query language in Cosmos DB (in Azure and Fabric)

The LEFT function returns the left part of a string up to the specified number of characters.

An Azure Cosmos DB system function that returns a substring from the left side of a string.

Syntax

LEFT(<string_expr>, <numeric_expr>)

Arguments

	Description
string_expr	A string expression.
numeric_expr	A numeric expression specifying the number of characters to extract from string_expr.

Return types

Returns a string expression.

Examples

This section contains examples of how to use this query language construct.

Get left part of string

In this example, the LEFT function is used to return the left part of the string AdventureWorks for various length values.

SELECT VALUE {
  firstZero: LEFT("AdventureWorks", 0),
  firstOne: LEFT("AdventureWorks", 1),
  firstFive: LEFT("AdventureWorks", 5),
  fullLength: LEFT("AdventureWorks", LENGTH("AdventureWorks")),
  beyondMaxLength: LEFT("AdventureWorks", 100)
}

[
  {
    "firstZero": "",
    "firstOne": "A",
    "firstFive": "Adven",
    "fullLength": "AdventureWorks",
    "beyondMaxLength": "AdventureWorks"
  }
]

Remarks

• This function benefits from the use of a range index. For more information, see range indexes.