SQL Server engine errors

SQL Server 8152 String or Binary Data Truncated

8152
MediumDatabase Engine

String or Binary Data Truncated — the value exceeds the column's defined length

What 8152 Means

The 8152 error on the SQL Server engine errors indicates string or binary data truncated — the value exceeds the column's defined length. This typically occurs due to inserting a string longer than the column's varchar or nvarchar size limit.

Error 8152 occurs when a value being inserted or updated is wider than the column's defined maximum length. SQL Server refuses to silently truncate data and raises this error to protect data integrity.

Technical Background

Error 8152 is a data integrity safeguard. When a VARCHAR(100) column receives a 150-character string, SQL Server raises this error rather than silently dropping the excess 50 characters. This behavior prevents hidden data loss.

In older SQL Server versions, the error message did not specify which column caused the truncation, making debugging batch inserts difficult. Newer versions and trace flag 460 provide verbose truncation messages that name the exact column and row.

Common Causes

  • Inserting a string longer than the column's VARCHAR or NVARCHAR size limit
  • A data migration feeds long-text values into a shorter target column
  • Concatenation in a computed expression produces output exceeding the destination width

Typical Scenarios

  • A user enters a 300-character comment into a field backed by a VARCHAR(255) column
  • An import script loads CSV records where one field exceeds the target column's width

What to Know

Identifying the specific column and value causing the truncation is the core diagnostic task. Enabling verbose truncation warnings (available in newer SQL Server versions) provides exact column-level detail in the error message.

Frequently Asked Questions

Common questions about SQL Server 8152 error

Silent truncation would destroy data without the application knowing. SQL Server protects data integrity by refusing the operation entirely and alerting the caller to the length mismatch.