Returns a pointer to the first page of a text, image, or unitext column.
textptr(column_name)
is the name of a text column.
Uses the textptr function to locate the text column, copy, associated with au_id 486-29-1786 in the author’s blurbs table. The text pointer is placed in local variable @val and supplied as a parameter to the readtext command, which returns 5 bytes, starting at the second byte (offset of 1):
declare @val binary(16) select @val = textptr(copy) from blurbs where au_id = "486-29-1786" readtext blurbs.copy @val 1 5
Selects the title_id column and the 16-byte text pointer of the copy column from the blurbs table:
select au_id, textptr(copy) from blurbs
textptr, a text and image function, returns the text pointer value, a 16-byte varbinary value.
If a text, unitext, or image column has not been initialized by a non-null insert or by any update statement, textptr returns a NULL pointer. Use textvalid to check whether a text pointer exists. You cannot use writetext or readtext without a valid text pointer.
For general information about text and image functions, see “Text and image functions”.
Trailing f
in varbinary values
are truncated when the values are stored in tables. If you are storing
text pointer values in a table, use binary as
the datatype for the column.
ANSI SQL – Compliance level: Transact-SQL extension.
Any user can execute textptr.
Datatypes text, image, and unitext datatypes
Function textvalid
Commands insert, update, readtext, writetext
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