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TEXTVALID (Transact-SQL)

A text, ntext, or image function that checks whether a specific text pointer is valid.

Important

This feature will be removed in a future version of Microsoft SQL Server. Avoid using this feature in new development work, and plan to modify applications that currently use this feature. Alternative functionality is not available.

Topic link iconTransact-SQL Syntax Conventions

Syntax

TEXTVALID ('table.column',text_ ptr )

Arguments

  • table
    Is the name of the table that will be used.

  • column
    Is the name of the column that will be used.

  • text_ptr
    Is the text pointer to be checked.

Return Types

int

Remarks

Returns 1 if the pointer is valid and 0 if the pointer is not valid. Note that the identifier for the text column must include the table name. You cannot use UPDATETEXT, WRITETEXT, or READTEXT without a valid text pointer.

The following functions and statements are also useful when you work with text, ntext, and image data.

Function or statement

Description

PATINDEX('%pattern%', expression)

Returns the character position of a specified character string in text and ntext columns.

DATALENGTH(expression)

Returns the length of data in text, ntext, and image columns.

SET TEXTSIZE

Returns the limit, in bytes, of the text, ntext, or image data to be returned with a SELECT statement.

Examples

The following example reports whether a valid text pointer exists for each value in the logo column of the pub_info table.

Note

To run this example, you must install the pubs database. For information about how to install the pubs database, see Downloading Northwind and pubs Sample Databases.

USE pubs;
GO
SELECT pub_id, 'Valid (if 1) Text data' 
   = TEXTVALID ('pub_info.logo', TEXTPTR(logo)) 
FROM pub_info
ORDER BY pub_id;
GO

Here is the result set.

pub_id Valid (if 1) Text data 
------ ---------------------- 
0736   1                      
0877   1                      
1389   1                      
1622   1                      
1756   1                      
9901   1                      
9952   1                      
9999   1                      

(8 row(s) affected)