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284. TRY_CAST Function

Learn how TRY_CAST safely attempts to convert values without failing the entire query for invalid conversions.

📘 Lesson 284 of 728 ⏱ 10 min 🎯 Intermediate

TRY_CAST attempts to convert an expression to a specified data type and returns NULL when the conversion cannot be performed, where supported by the database.

Real-world datasets often contain invalid or inconsistent values. TRY_CAST can help identify problematic records without stopping the entire query.

Safely convert a text salary field into a numeric value.

SQL 
SELECT
    EmployeeName,
    TRY_CAST(SalaryText AS DECIMAL(12,2)) AS SalaryAmount
FROM EmployeeImport;

TRY_CAST is useful in data cleaning, ETL processes, validation, and handling inconsistent imported data.

  • TRY_CAST attempts a data type conversion.
  • Invalid conversions can return NULL.
  • It can prevent conversion errors.
  • It is useful for data-quality checks.
  • Database support varies.
What is TRY_CAST used for?

TRY_CAST attempts a conversion and returns NULL when the conversion cannot be completed.

Why is TRY_CAST useful in data cleaning?

It allows invalid values to be identified without causing the entire query to fail.

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