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For security reasons we should always use parameterized queries to avoid SQL injections through parameters. The usual format is When a PostgreSQL command runs and a parameter is not used, we get the error message error: could not determine data type of parameter $1 Solution: Remove the unused parameter from the “parameters” array, in this …
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If your Next.js React TypeScript web application uses database calls to display data on the pages, and during build time the database is not available, we need to disable the static page generation, otherwise we get the following error: info Generating static pages…TypeError: Failed to parse URL from ……code: ‘ERR_INVALID_URL’ To disable the static page …
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If your application is in the proof of concept phase, it works and you just want to build it, you can disable the linting process to have a successful build regardless of linting errors.
The ESLint static code analysis tool flags code where we operate on objects which can be undefined. Object is possibly ‘undefined’ The end of the red line shows the extent of the object which can be undefined, as the “children” element is defined as optional in the type definition: To satisfy the linter, we need to …
When you create an array in TypeScript the type of the first element defines the type of all elements of the array. When we reuse an array with new data, the array type has already been defined, so when we assign new values to the same array we get the error message: Type error: Type …
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In a TypeScript application ESLint flags code when we try to assign “null” value to string type variables and attributes. This can be necessary when we want to set the value of a database column to “null”. To make a string type attribute nullable, add ” | null ” to the type definition:
If you use the VirtualTable in a React TypeScript web application ESLint will throw an error when it checks the VirtuosoTableComponents. Error: Component definition is missing display name react/display-name The Virtuoso component uses arrow functions to declare the Scroller and TableBody. Arrow functions do not provide the displayName property used by developer tools. We can modify the component to …
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We can use simple CSS settings to scroll cards horizontally in a container. Apply these settings to the container <div>: Configure the card <div>s with this:
Identity columns There are three auto incremented identity columns types in PostgreSQL Name Storage Range SMALLSERIAL 2 bytes 1 to 32,767 SERIAL 4 bytes 1 to 2,147,483,647 BIGSERIAL 8 bytes 1 to 9,223,372,036,854,775,807 To create a new identity column use the following syntax
In a Next.js React web application we can export functionality two ways: The two definitions have to be imported with two different syntaxes If we try to use the wrong import statement, we get the following error message: Make sure your import statement matches the definition format.