In computer programming, create, read, update and delete (CRUD) are the four basic functions of persistent storage. Sometimes CRUD is expanded with the words retrieve instead of read or destroy instead of delete. It is also sometimes used to describe user interface conventions that facilitate viewing, searching, and changing information; often using computer-based forms and reports. The term was likely first popularized by James Martin in a 1983 book titled “Managing the Data-base Environment”.

Database applications

The acronym CRUD refers to all of the major functions that are implemented in relational database applications, that are considered as complete application. Each letter in the acronym is mapped to a standard SQL statement:

Although a relational database is a common persistence layer in software applications, there are numerous others. CRUD can be implemented with an object database, an XML database, flat text files, custom file formats, tape, or card, for example.

User interface

CRUD is also relevant at the user interface level of most applications. For example, in address book software, the basic storage unit is an individual contact entry. As a bare minimum, the software must allow the user to:

• Create or add new entries
• Read, retrieve, search, or view existing entries
• Update or edit existing entries
• Delete existing entries

Without at least these four operations, the software cannot be considered complete. Because these operations are so fundamental, they are often documented and described under one comprehensive heading, such as “contact management” or “contact maintenance” (or “document management” in general, depending on the basic storage unit for the particular application).

In computer programming, create, read, update and delete (CRUD) are the four basic functions of persistent storage. Sometimes CRUD is expanded with the words retrieve instead of read or destroy instead of delete. It is also sometimes used to describe user interface conventions that facilitate viewing, searching, and changing information; often using computer-based forms and reports. The term was likely first popularized by James Martin in a 1983 book titled “Managing the Data-base Environment”.

Database applications

The acronym CRUD refers to all of the major functions that are implemented in relational database applications, that are considered as complete application. Each letter in the acronym is mapped to a standard SQL statement:

Although a relational database is a common persistence layer in software applications, there are numerous others. CRUD can be implemented with an object database, an XML database, flat text files, custom file formats, tape, or card, for example.

User interface

CRUD is also relevant at the user interface level of most applications. For example, in address book software, the basic storage unit is an individual contact entry. As a bare minimum, the software must allow the user to:

• Create or add new entries
• Read, retrieve, search, or view existing entries
• Update or edit existing entries
• Delete existing entries

Without at least these four operations, the software cannot be considered complete. Because these operations are so fundamental, they are often documented and described under one comprehensive heading, such as “contact management” or “contact maintenance” (or “document management” in general, depending on the basic storage unit for the particular application).

Delegation is an essential part of a project manager’s role, so identifying roles and responsibilities early in a project is important. Applying the RACI model can help. As project manager it is important that you set the expectations of people involved in your project from the outset.

Projects require many people’s involvement, but how do you avoid a situation where people are struggling against one another to do a task. Equally difficult is dealing with a situation where nobody will take ownership and make a decision. How do people know their level of responsibility; when they should involve you as their project manager, or when they should exercise their own judgment?

The RACI model is a straightforward tool used for identifying roles and responsibilities and avoiding confusion over those roles and responsibilities during a project. The acronym RACI stands for:

• Responsible: The person who does the work to achieve the task. They have responsibility for getting the work done or decision made. As a rule this is one person; examples might be a business analyst, application developer or technical architect.
• Accountable: The person who is accountable for the correct and thorough completion of the task. This must be one person and is often the project executive or project sponsor. This is the role that responsible is accountable to and approves their work.
• Consulted: The people who provide information for the project and with whom there is two-way communication. This is usually several people, often subject matter experts.
• Informed: The people who are kept informed about progress and with whom there is one-way communication. These are people that are affected by the outcome of the tasks so need to be kept up-to-date.

Without clearly defined roles and responsibilities it is easy for projects to run into trouble. When people know exactly what is expected of them, it is easier for them to complete their work on time, within budget and to the right level of quality.

A RACI matrix supports the model and is used to discuss, agree and communicate roles and responsibilities.

Creating a RACI Matrix (step-by-step)

1. Identify all the tasks involved in delivering the project and list them on the left-hand side of the chart in completion order.
2. Identify all the project roles and list them along the top of the chart.
3. Complete the cells of the chart identifying who has responsibility, accountability and who will be consulted and informed for each task.
4. Ensure every task has a role responsible and a role accountable for it.
5. No tasks should have more than one role accountable. Resolve any conflicts where there is more than one for a particular task.
6. Share, discuss and agree the RACI Matrix with your stakeholders before your project starts.

A variation of RACI used by the Project Management Institute (PMI) is RSI, responsible, sponsor and informed.

Other variations are:

• RASCI: with the ‘S’ standing for ‘Support’
• RACIO: with the ‘O’ standing for ‘Out of the Loop’ or ‘Omitted’
• RACI-VS: with the ‘V’ standing for ‘Verify’ and the ‘S’ for ‘Signatory’

Delegation is an essential part of a project manager’s role, so identifying roles and responsibilities early in a project is important. Applying the RACI model can help. As project manager it is important that you set the expectations of people involved in your project from the outset.

Projects require many people’s involvement, but how do you avoid a situation where people are struggling against one another to do a task. Equally difficult is dealing with a situation where nobody will take ownership and make a decision. How do people know their level of responsibility; when they should involve you as their project manager, or when they should exercise their own judgment?

The RACI model is a straightforward tool used for identifying roles and responsibilities and avoiding confusion over those roles and responsibilities during a project. The acronym RACI stands for:

• Responsible: The person who does the work to achieve the task. They have responsibility for getting the work done or decision made. As a rule this is one person; examples might be a business analyst, application developer or technical architect.
• Accountable: The person who is accountable for the correct and thorough completion of the task. This must be one person and is often the project executive or project sponsor. This is the role that responsible is accountable to and approves their work.
• Consulted: The people who provide information for the project and with whom there is two-way communication. This is usually several people, often subject matter experts.
• Informed: The people who are kept informed about progress and with whom there is one-way communication. These are people that are affected by the outcome of the tasks so need to be kept up-to-date.

Without clearly defined roles and responsibilities it is easy for projects to run into trouble. When people know exactly what is expected of them, it is easier for them to complete their work on time, within budget and to the right level of quality.

A RACI matrix supports the model and is used to discuss, agree and communicate roles and responsibilities.

Creating a RACI Matrix (step-by-step)

1. Identify all the tasks involved in delivering the project and list them on the left-hand side of the chart in completion order.
2. Identify all the project roles and list them along the top of the chart.
3. Complete the cells of the chart identifying who has responsibility, accountability and who will be consulted and informed for each task.
4. Ensure every task has a role responsible and a role accountable for it.
5. No tasks should have more than one role accountable. Resolve any conflicts where there is more than one for a particular task.
6. Share, discuss and agree the RACI Matrix with your stakeholders before your project starts.

A variation of RACI used by the Project Management Institute (PMI) is RSI, responsible, sponsor and informed.

Other variations are:

• RASCI: with the ‘S’ standing for ‘Support’
• RACIO: with the ‘O’ standing for ‘Out of the Loop’ or ‘Omitted’
• RACI-VS: with the ‘V’ standing for ‘Verify’ and the ‘S’ for ‘Signatory’

A System Context Diagram (SCD) in software engineering and systems engineering is a diagram that represents the actors outside a system that could interact with that system. This diagram is the highest level view of a system. It is similar to a Block diagram. SCDs show a system, often software-based, as a whole and its inputs and outputs from/to external factors.

Document Management Sytem Context Diagrams Visio File Download

A data flow diagram (DFD) is a graphical representation of the “flow” of data through an information system, modelling its process aspects. Often they are a preliminary step used to create an overview of the system which can later be elaborated. DFDs can also be used for the visualization of data processing (structured design).

A DFD shows what kinds of data will be input to and output from the system, where the data will come from and go to, and where the data will be stored. It does not show information about the timing of processes, or information about whether processes will operate in sequence or in parallel (which is shown on a flowchart).

It is common practice to draw the context-level data flow diagram first, which shows the interaction between the system and external agents which act as data sources and data sinks. On the context diagram the system’s interactions with the outside world are modelled purely in terms of data flows across the system boundary. The context diagram shows the entire system as a single process, and gives no clues as to its internal organization.

This context-level DFD is next “exploded”, to produce a Level 0 DFD that shows some of the detail of the system being modeled. The Level 0 DFD shows how the system is divided into sub-systems (processes), each of which deals with one or more of the data flows to or from an external agent, and which together provide all of the functionality of the system as a whole. It also identifies internal data stores that must be present in order for the system to do its job, and shows the flow of data between the various parts of the system.

Data flow diagrams were proposed by Larry Constantine, the original developer of structured design, based on Martin and Estrin’s “data flow graph” model of computation.

Data flow diagrams (DFDs) are one of the three essential perspectives of the structured-systems analysis and design method SSADM. The sponsor of a project and the end users will need to be briefed and consulted throughout all stages of a system’s evolution. With a data flow diagram, users are able to visualize how the system will operate, what the system will accomplish, and how the system will be implemented. The old system’s dataflow diagrams can be drawn up and compared with the new system’s data flow diagrams to draw comparisons to implement a more efficient system. Data flow diagrams can be used to provide the end user with a physical idea of where the data they input ultimately has an effect upon the structure of the whole system from order to dispatch to report. How any system is developed can be determined through a data flow diagram.

In the course of developing a set of levelled data flow diagrams the analyst/designers is forced to address how the system may be decomposed into component sub-systems, and to identify the transaction data in the data model.

There are different notations to draw data flow diagrams (Yourdon & Coad and Gane & Sarson), defining different visual representations for processes, data stores, data flow, and external entities.