Page:: delete()

Is a method to remove a record from both the display screen and the database of the user

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    async delete(): Promise<void> {

Description

To reveal the entity and database name, de-structure this page's subject.

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        const [ename, dbname] = this.subject;

Get the selected table-row if any is selected and otherwise alert the user to make a selection

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       const tr = this.document.querySelector(".TR");
        if (tr === null) { 
            alert("Please select a row to delete");
            return;
        }

Get the primary key of the currently selected record .

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        const pk = tr.getAttribute("pk");

Ensure that the entity name is enclosed with backticks and then formulate a SQL statement to perform the deletion.

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        const ename_str = `\`${ename}\``;
        const sql = `Delete  from ${ename_str}  where ${ename_str}
        .${ename_str}='${pk}'`;

Execute the delete query on the server and return the number of affected records.

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     const records = await server.exec("database", [dbname], "query", [sql]);

Finally check if the deletion was successful, if not report an error(mutall_error).

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     if (records !== 1) {
         throw new schema.mutall_error(`The following query was not successful:
          ${sql}`);
     }

Refresh the homepage to reflect/show the changes that have been carried out i.e. remove the row from the table in the user interface.

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     tr.parentNode!.removeChild(tr);
 }