Author: Ian

Fix ERROR 1045: “Access denied for user…” in MySQL

Posted on by Ian

If you’re getting error 1045 that reads something like “Access denied for user ‘root’@’localhost’“, it’s because you’re trying to log in to MySQL without the right credentials.

This usually happens when we provide the wrong password. But there could also be another cause. For example, we could be trying to do something as the root user that requires a password, but the root user hasn’t yet had its password set.

To fix this issue, be sure to provide the correct password when connecting to MySQL.

Continue reading →

How to Include Elements that Contain NULL Values When Using FOR XML in SQL Server

Posted on by Ian

When using FOR XML in SQL Server, we can use the ELEMENTS directive to include a column as an element instead of an attribute. However by default, if a column contains a NULL value, no element is produced for that column in the resulting XML document. This may or may not be what we want, depending on the requirements.

If we want such columns to be included in the XML even when they contain NULL values, all we need to do is include the XSINIL option. This option specifies that any column that has a NULL value automatically gets an element with xsi:nil="true" in the resulting XML.

The alternative is ABSENT, which means columns with NULL values are excluded (this is the default behaviour).

Continue reading →

How to Include Elements that Contain NULL Values When Using FOR XML EXPLICIT in SQL Server

Posted on by Ian

When using FOR XML EXPLICIT in SQL Server, we can use the ELEMENT directive to include a column as an element instead of an attribute. However, this directive doesn’t allow for NULL values. What I mean is that if a column contains a NULL value, no element is produced for that column in the resulting XML document. This may or may not be what we want, depending on the requirements.

If we want such columns to be included in the XML even when they contain NULL values, we can use the ELEMENTXSINIL directive instead of ELEMENT.

Continue reading →

SQL Server FOR XML EXPLICIT Examples

Posted on by Ian

In SQL Server, the FOR XML clause allows us to return the results of a query as an XML document. Simply by placing the FOR XML clause at the end of the query will output the results in XML.

When we do this, we have the option of specifying RAW, AUTO, EXPLICIT, or PATH mode. These modes allow us to shape the resulting XML in different ways, and so the mode we choose will determine how the XML is generated.

Below are examples of using EXPLICIT mode when generating XML from a SQL query.

Continue reading →

SQL Server FOR XML RAW Examples

Posted on by Ian

In SQL Server, the FOR XML clause allows us to return the results of a query as an XML document. Simply by placing the FOR XML clause at the end of the query will output the results in XML.

When we do this, we have the option of specifying RAW, AUTO, EXPLICIT, or PATH mode. These modes allow us to shape the resulting XML in different ways, and so the mode we choose will determine how the XML is generated.

Below are examples of using RAW mode when generating XML from a SQL query.

Continue reading →

Fix “ERR wrong number of arguments for ‘srandmember’ command” in Redis

Posted on by Ian

If you’re getting an error that reads “ERR wrong number of arguments for ‘srandmember’ command” in Redis, it’s probably because you’re calling the SRANDMEMBER command without any arguments.

To fix this issue, make sure you pass the correct number of arguments. At the time of writing, the SRANDMEMBER command requires at least one argument, and accepts an optional second argument.

Continue reading →