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5 minutes read
In SPARQL, filters are used to restrict the results of a query based on certain conditions. If you want to build a case-insensitive filter in SPARQL, you can use the str functions provided by SPARQL to convert the strings to lowercase or uppercase before comparing them.For example, if you want to filter results based on a specific string regardless of its case, you can use the following query:SELECT ?entity WHERE { ?entity rdf:type dbo:Person . FILTER(LCASE(STR(.
3 minutes read
To get the days between two dates using SPARQL, you can use the xsd:date and xsd:integer functions provided by SPARQL. First, convert the two dates to xsd:date format using the xsd:date function. Then, subtract the two dates to get the number of days between them. Finally, convert the result to an integer using the xsd:integer function. This will give you the days between the two dates.What is the output format for displaying the days between two dates using SPARQL.
4 minutes read
GraphQL and SPARQL are both query languages used for retrieving information from databases or APIs, but they have some key differences.GraphQL is primarily used for querying and manipulating data within web APIs. It allows users to describe the structure of the data they want in a flexible way, enabling clients to request only the data they need. GraphQL is typically used in front-end development to fetch data for web and mobile applications.
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In SPARQL, you can ignore values by using the "FILTER" clause along with the "!" operator which signifies negation. This allows you to filter out certain values from the query results based on conditions you specify. Ignoring values in SPARQL can help you to focus on the data that is relevant to your specific query and exclude unwanted results.
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To run a SPARQL spatial query, you first need to have a dataset that includes spatial data. You can use a triple store like Virtuoso or Apache Jena to store your RDF data.SPARQL has built-in support for querying spatial data using the GeoSPARQL extension. In order to run a SPARQL spatial query, you need to use the GeoSPARQL functions and predicates in your query.For example, you can use the "sfWithin" function to find all the entities that are located within a specific spatial region.
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To get results using a customized ORDER BY query with SPARQL, you first need to understand the basics of SPARQL syntax and query structure. The ORDER BY clause in SPARQL is used to sort the results of a query based on specified criteria. To customize the ORDER BY query, you can use various functions and operators to define the sorting criteria, such as ascending or descending order, and specify multiple variables for sorting.
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Translating a SPARQL query into English involves breaking down the query into its individual components and interpreting them into human-readable language. This process requires understanding the structure of the query, including the SELECT statement which specifies the variables to retrieve, the WHERE clause which filters the results based on specified conditions, and the prefix declarations which define the namespaces used in the query.
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To perform a SPARQL update with Perl, you can use the RDF::Query::Client module which provides a simple API for interacting with SPARQL endpoints. First, you would establish a connection to the SPARQL endpoint using RDF::Query::Client's new constructor method. Then, you can issue SPARQL update queries using the update_query method. This method takes the SPARQL update query as a parameter and executes it against the endpoint.
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To recursively query with SPARQL, you can use the OPTIONAL keyword to perform a recursive query in a graph database. This allows you to retrieve connected data by following relationships between nodes in the graph. By using OPTIONAL, you can specify conditions for the relationship between nodes, and the query will retrieve data that meets those conditions, including data that is connected through other nodes in the graph.
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In SPARQL, you can bind a string with a variable using the BIND keyword. You can use the BIND keyword followed by the variable you want to bind the string to and then specify the string value within quotes. For example, if you want to bind the string "example" to the variable ?str, you can do so with the following SPARQL query:SELECT ?str BIND("example" AS ?str)This will bind the string "example" to the variable ?str in your SPARQL query results.