Caché MultiValue PROC Reference
FB, FBU
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Opens a file and reads a record into the fast file buffer.
Synopsis
FB [(][DICT] filename [itemId][)]

FBU [(][DICT] filename [itemId][)]
Arguments
filename The name of the file to read into the fast file buffer. filename can be a literal, or a reference to a buffer or a select list that contains the filename.
itemId Optional — The item ID of the item to be read into the fast file buffer. itemId can be a literal, or a reference to a buffer or a select list that contains the item ID. If you do not specify an itemId, FB selects the current item.
Description
The FB PROC command opens a file and reads a single record. This record is read into the fast file buffer. The fast file buffer is referenced as & or &0. This command has two forms, FB (simple read) and FBU (read with update lock). A subsequent FB command overwrites the contents of the fast file buffer.
You can use the optional DICT keyword to specify that the file is a dictionary file. The DICT keyword can be supplied as a literal, or indirectly.
The enclosing parentheses are optional in Caché MultiValue. They are required in some MultiValue implementations and are not permitted in other MultiValue implementations.
FB is functionally equivalent to an F-OPEN followed by an F-READ. FBU is functionally equivalent to an F-OPEN followed by an F-UREAD. An item locked with FBU can be unlocked using F-FREE.
This is a PQN command.
See Also