Validating date in php
The check step uses one or more computational rules (see section below) to determine if the data is valid.The Post-validation action sends feedback to help enforce validation.
Code and cross-reference validation includes tests for data type validation, combined with one or more operations to verify that the user-supplied data is consistent with one or more external rules, requirements, or validity constraints relevant to a particular organization, context or set of underlying assumptions.A more sophisticated data validation routine would check to see the user had entered a valid country code, i.e., that the number of digits entered matched the convention for the country or area specified.A validation process involves two distinct steps: (a) Validation Check and (b) Post-Check action.The data may be represented differently in different systems and may need to be transformed to a common format to be compared, e.g., one system may store customer name in a single Name field as 'Doe, John Q', while another in three different fields: First_Name (John), Last_Name (Doe) and Middle_Name (Quality); to compare the two, the validation engine would have to transform data from the second system to match the data from the first, for example, using SQL: Last_Name || ', ' || First_Name || substr(Middle_Name, 1, 1) would convert the data from the second system to look like the data from the first 'Doe, John Q'Checks the data type of the input and give an error message if the input data does not match with the chosen data type, e.g., In an input box accepting numeric data, if the letter 'O' was typed instead of the number zero, an error message would appear.In modern Relational database values in two tables can be linked through foreign key and primary key.Checks to ascertain that only expected characters are present in a field.
For example a numeric field may only allow the digits 0–9, the decimal point and perhaps a minus sign or commas.
Data validation rules can be defined and designed using any of various methodologies, and be deployed in any of various contexts.
Data validation rules may be defined, designed and deployed, for example: Definition and design contexts: Data that does not conform to these rules will negatively affect business process execution.
Caution: The documentation you are viewing is for an older version of Zend Framework.
In computer science, data validation is the process of ensuring that data have undergone data cleansing to ensure they have data quality, that is, that they are both correct and useful.
Therefore, data validation should start with business process definition and set of business rules within this process.