If you get an error that reads “WRONGTYPE Operation against a key holding the wrong kind of value” when using the ZINTERSTORE command in Redis, it’s probably because you’re passing a key with the wrong data type.
To fix this issue, be sure that each key you pass to the ZINTERSTORE command is either a set or a sorted set.
SQL Server sequence objects allow us to increment or decrement through a range of numbers. Once set, we don’t need to change anything. We can simply use NEXT VALUE FOR to generated the next sequential number.
But what if we want to change the sequence to use a different range?
For example, we created a sequence that increments between 0 and 100, but now we want to change it to increment between 200 and 300.
Easy. We can use the ALTER SEQUENCE statement to do just that.
Some RDBMSs provide an easy way for us to find out how many rows were affected by the last SQL statement. This can be handy when running INSERT, UPDATE, or DELETE statements.
The method used depends on the DBMS we’re using. Below, I look at how some of the major DBMSs implement this functionality.
Continue readingIf you’re getting SQL Server error Msg 529 that reads Explicit conversion from data type date to int is not allowed, it’s because you’re trying to explicitly convert a date data type to an int data type, which is not allowed in SQL Server.
To fix this issue, try converting the date value to a string first, and then to an integer.
Alternatively, change the destination type to one that’s allowed.
Also, check that you’re trying to convert the correct value. For example, you may have selected the wrong column or variable. In this case, selecting the correct column may fix the problem.
Continue readingIf you’re getting an error that reads something like “START value (11) cannot be greater than MAXVALUE (10)” in PostgreSQL when you’re trying to create a sequence, it’s because your sequence’s start value is higher than its maximum value, when it should be lower or the same.
To fix this issue, be sure that the sequence’s maximum value is not less than its start value.
Continue readingBy default, time zone names aren’t included with MySQL. The MySQL installation process creates the appropriate tables, but it doesn’t populate these tables.
That said, it’s very easy to populate these tables.
Once populated, we can list out the time zone names available in our system by querying the mysql.time_zone_name table.
In MySQL and MariaDB we can use the AUTO_INCREMENT keyword to create an automatically incrementing column in a table. In SQLite, we’d use the AUTOINCREMENT keyword. And in SQL Server we can use the IDENTITY property. Some of those DBMSs also allow us to create sequence objects, which provide us with more options for creating an auto-increment type column.
When it comes to PostgreSQL, there are a few ways to create an auto-incrementing column. Below are three options for creating an AUTO_INCREMENT style column in Postgres.
If you’re getting error msg 8115 that includes the message Arithmetic overflow error converting expression to data type…, it’s probably because you’re trying to convert a value to a data type that can’t handle that value. For example, trying to convert a number to a tinyint but the number’s too big to fit into a tinyint.
To fix this issue, make sure you convert the value to a data type that can handle the size of the value that you’re trying to convert.
Continue readingPostgreSQL allows us to create sequence objects, otherwise known as “sequence generators”, or simply “sequences”. As the name suggests, a sequence object is used to generate sequence numbers.
We can use sequences to generate incrementing numbers or decrementing numbers.
Continue readingIf you’re getting error msg 9809 which reads something like The style … is not supported for conversions from … to … in SQL Server, it’s probably because you’re trying to convert between data types, but the style that you’re specifying isn’t supported for that operation.
It’s not that the conversion can’t happen, it’s just that the style that you’re providing is wrong.
Continue reading