TRY_CAST

​

Syntax

​

Scalar

try_cast(value AS target_type)

​

Arguments

​

Returns

• Type: Requested target SQL type
• NULL behavior: A NULL value remains NULL for a supported conversion. A failed supported value conversion produces NULL.

​

Properties

​

Usage notes

• Write the target type directly in the call. It cannot be a STRING expression that changes for each row.
• INTEGER and INT mean the same type; STRING means VARCHAR text. NULL can be used with a supported type. Cast NULL explicitly when its type would otherwise be unclear.
• Not every source type can be converted to every target type. MAP-to-STRING and STRUCT-to-STRING conversions are rejected. Casting ARRAY, MAP, or STRUCT does not recursively convert its elements or fields.
• Deterministic: The same inputs and settings produce the same result.

​

Examples

​

Typical behavior

SELECT TRY_CAST('42' AS INT) AS "value", TRY_CAST(CAST(NULL AS STRING) AS INT) AS null_value;

​

Handle invalid values in different target types

SELECT TRY_CAST('12.50' AS DECIMAL(8,2)) AS price, TRY_CAST('not-a-date' AS DATE) AS invalid_date;

​

Limitations

• Unsupported conversions or incomplete target-type definitions can cause the query to be rejected before execution. TRY_CAST does not turn those errors into NULL.
• CHAR and VARCHAR length limits are not enforced by this cast. Do not rely on the cast to truncate text.

​

Related functions

• typeof
• cast