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Bonus Appendix 1: System Functions > Text and Image Functions
The text and image functions perform operations on text or image data. They are:
- TEXTPTR
- TEXTVALID
TEXTPTR
The TEXTPTR function checks the value of the text pointer that corresponds to a text, ntext, or image column and returns a varbinary value. The text pointer should be checked to ensure that it points to the first text page before running READTEXT, WRITETEXT, and UPDATE statements. The syntax is as follows:
TEXTPTR(<column>)
TEXTVALID
The TEXTVALID function checks whether a specified text pointer is valid. The syntax is as follows:
TEXTVALID('<table.column>', <text_pointer>)
The table.column parameter specifies the name of the table and column to be used. The text_pointer parameter specifies the text pointer to be checked.