Remove PF Constraint (RMVPFCST)

Remove PF Constraint (RMVPFCST)

Where allowed to run: All environments (*ALL)
Threadsafe: Conditional Parameters
Examples
Error messages

The Remove Physical File Constraint (RMVPFCST) command can be used to remove one or more constraint relationships between physical files. The constraint relationships that can be removed with this command are referential constraints, unique constraints, primary key constraints, and check constraints.
Restrictions:

You must have object management (*OBJMGT) or object alter (*OBJALTER) authority to the physical file specified for the File (FILE) parameter.
You must have execute (*EXECUTE) authority to the library that contains the physical file.
You cannot remove a constraint relationship from a file that your user job has open.
This command is conditionally threadsafe. In multithreaded jobs, this command is not threadsafe for distributed files and fails for distributed files that use relational databases of type *SNA.

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Parameters

Keyword Description Choices Notes
FILE File Qualified object name Required, Positional 1
Qualifier 1: File Name
Qualifier 2: Library Name, *LIBL, *CURLIB
CST Constraint name Single values: *ALL, *CHKPND
Other values (up to 300 repetitions): Character value Required, Positional 2
TYPE Constraint type *ALL, *REFCST, *UNQCST, *PRIKEY, *CHKCST Optional, Positional 3
RMVCST Remove constraint *RESTRICT, *REMOVE, *KEEP Optional

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File (FILE)

Specifies the physical file from which a constraint is to be removed. For a referential constraint, this file can be a dependent file only.
This is a required parameter.
Qualifier 1: File

name

Specify the name of the physical file.

Qualifier 2: Library

*LIBL

All libraries in the library list for the current thread are searched until the first match is found.

*CURLIB

The current library for the job is searched. If no library is specified as the current library for the job, the QGPL library is used.

name

Specify the name of the library to be searched.

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Constraint name (CST)

Specifies the name of the constraint relationship being removed.
This is a required parameter.
Single values

*ALL

All of the constraint relationships for the file specified on the FILE parameter are removed.

*CHKPND

The constraint relationships that have records that are possibly in violation of the constraints (check pending) are removed. A check pending state occurs when the system has not yet determined that the values of a dependent file are all valid in relation to its parent key or record values for the check constraint expression are valid. Only referential and check constraints can be in check pending.

Other values (up to 300 repetitions)

character-value

Specify the name of the constraint.

The case is preserved when lowercase characters are specified.

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Constraint type (TYPE)

Specifies the type of constraint relationship named on the CST parameter that is being removed from the physical file.

*ALL

All types of primary key and unique constraints are removed. The following are examples of the CST parameter dependencies:

CST(*ALL) TYPE(*ALL) - All constraints are removed
CST(*CHKPND) TYPE(*ALL) - All referential and check constraints in check pending are removed
CST(ABC) TYPE(*ALL) - The constraint ABC is removed

This value is ignored for referential constraints when the RMVCST parameter is specified.

*REFCST

The referential constraints are removed. The following are examples of the CST parameter dependencies:

CST(*ALL) TYPE(*REFCST) - All referential constraints are removed
CST(*CHKPND) TYPE(*REFCST) - All referential constraints in check pending are removed
CST(ABC) TYPE(*REFCST) - The referential constraint ABC is removed

*UNQCST

The unique constraints are removed.

If the unique constraint is a primary key, the unique constraint is removed, but the primary key definition and the file's access path are not removed.
The following are examples of the CST parameter dependencies:

CST(*ALL) TYPE(*UNQCST) - All unique constraints (except the primary key constraint) are removed
CST(*CHKPND) TYPE(*UNQCST) - Not valid; unique constraints cannot be in check pending
CST(ABC) TYPE(*UNQCST) - The unique constraint ABC is removed (unless it is a primary key constraint)

*PRIKEY

The primary key constraint is removed. The following are examples of the CST parameter dependencies:

CST(*ALL) TYPE(*PRIKEY) - The primary key constraint is removed
CST(*CHKPND) TYPE(*PRIKEY) - Not valid; primary key constraints cannot be in check pending
CST(ABC) TYPE(*PRIKEY) - The primary key constraint ABC is removed

*CHKCST

The check constraints are removed. The following are examples of the CST parameter dependencies:

CST(*ALL) TYPE(*CHKCST) - All check constraints are removed
CST(*CHKPND) TYPE(*CHKCST) - All check constraints in check pending are removed
CST(XYZ) TYPE(*CHKCST) - The check constraint XYZ is removed

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Remove constraint (RMVCST)

Specifies how much of the constraint relationship on the dependent file is removed when a primary key or unique constraint that is also a parent key is removed from the parent file of a referential constraint.

This parameter is ignored if *REFCST is specified for the Constraint type (TYPE) parameter.

*RESTRICT

The constraint is not removed if the constraint is either defined or established between the parent file and the dependent file. Neither the foreign key access path nor the foreign key of the dependent file is removed.

*REMOVE

The constraint and the constraint definition between the parent file and the dependent file are removed. The corresponding foreign key is removed. The foreign key access path of the dependent file is removed only if one exists and is not shared.

*KEEP

The constraint between the parent file and the dependent file is removed, but the constraint definition is not removed. The corresponding foreign key and the foreign key access path of the dependent file are not removed.

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Examples

In these examples, the unique constraint UNIQUE_Department_NUMBER and the referential constraint EMPLOYEE_Department were added to the files by issuing the following Add Physical File Constraint (ADDPFCST) commands:
 ADDPFCST   FILE(MYLIB/DEPARTMENTS)  TYPE(*UNQCST)
           KEY(DEPTNUM)  CST(UNIQUE_Department_NUMBER)
ADDPFCST   FILE(MYLIB/PERSONNEL)  TYPE(*REFCST)  KEY(DEPTNO)
           CST(EMPLOYEE_Department)
Example 1: Removing a Unique Constraint
 RMVPFCST   FILE(MYLIB/DEPARTMENTS)  CST(*ALL)  TYPE(*ALL)
This command removes the unique constraint UNIQUE_Department_NUMBER from the file DEPARTMENTS located in the library MYLIB.
Example 2: Removing a Referential Constraint
 RMVPFCST   FILE(MYLIB/PERSONNEL)  CST(EMPLOYEE_Department)
           TYPE(*REFCST)  RMVCST(*RESTRICT)
This command removes the referential constraint EMPLOYEE_Department from the dependent file PERSONNEL located in the library MYLIB. Because the parent file had not yet been established (the PRNFILE had not been specified on the ADDPFCST command) the removal is not restricted.

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Error messages

*ESCAPE Messages

CPF32B1

Constraint(s) not removed from file &1.

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Keyword	Description	Choices	Notes
FILE	File	Qualified object name	Required, Positional 1
	Qualifier 1: File	Name
	Qualifier 2: Library	Name, LIBL, CURLIB
CST	Constraint name	Single values: ALL, CHKPND Other values (up to 300 repetitions): Character value	Required, Positional 2
TYPE	Constraint type	ALL, REFCST, UNQCST, PRIKEY, *CHKCST	Optional, Positional 3
RMVCST	Remove constraint	RESTRICT, REMOVE, *KEEP	Optional