If you’re getting an error in PostgreSQL that tells you that a column “…can only be updated to DEFAULT” with detail that explains that it “…is an identity column defined as GENERATED ALWAYS“, it’s probably because you’re trying to update an identity column with your own value, but the identity column was created with the GENERATED ALWAYS
option.
Tag: errors
6 Ways to Fix “nextval: reached minimum value of sequence” in PostgreSQL
If you’re getting an error that reads something like “nextval: reached minimum value of sequence “sequence1” (-3)” in PostgreSQL, it’s probably because you’re trying to generate a new value from a descending sequence, but the sequence has already reached its minimum value.
We have a number options when it comes to dealing with this issue.
Continue reading6 Ways to Fix Error 1055 “Expression … of SELECT list is not in GROUP BY clause and contains nonaggregated column…” in MySQL
If you’ve been using MySQL for any decent amount of time, it’s likely you’ll be familiar with error 1055 that reads something like “Expression #N of SELECT list is not in GROUP BY clause and contains nonaggregated column…“, where #N
is the expression number of an expression/column in your SELECT
list.
This error can occur when we include a column in the SELECT
list, but we omit it from the GROUP BY
clause.
There are several ways we can go about resolving this issue. Below are six options for dealing with this issue.
Continue reading4 Ways to Fix Error 1048 “Column ‘…’ cannot be null” in MySQL
If you’re getting error 1048 that reads something like “Column ‘ColumnName’ cannot be null” (where ColumnName is the name of a column you’re trying to insert data into), then it’s probably because you’re trying to insert a NULL
value into that column, but the column has a NOT NULL
constraint (which prevents NULL
values from being inserted).
We have a few options when it comes to fixing this issue. The most obvious is to ensure we provide a non-NULL
value for the column. Alternatively, if the column should be able to accept NULL
values, then we can remove the NOT NULL
constraint from the column. Another option is to use the IGNORE
keyword to ignore the error. And another way to deal with the error is to disable strict mode.
MySQL IGNORE Clause Explained
In MySQL, we can use the IGNORE
clause in statements that change data in order to ignore certain errors that might occur had we not used it. When IGNORE
is used, such errors are downgraded to warnings.
For example, we can use IGNORE
in an INSERT
statement to ignore any errors we might normally get if we tried to insert a NULL
value into a NOT NULL
column. In such a case, MySQL won’t return an error. Instead, it will deal with the issue in another way, and provide us with a warning.
If we have strict mode enabled, we can use IGNORE
to force MySQL to act as though strict mode is disabled. However, IGNORE
can also be used to downgrade certain errors regardless of the strict mode setting.
Fix “ERROR: step size cannot equal zero” When Creating a PostgreSQL Series
If you’re getting an error that reads “step size cannot equal zero” when creating a series with the generate_series()
function in PostgreSQL, it’s because you’re using a step size of 0
(i.e. zero).
The generate_series()
function doesn’t accept a zero step size.
To fix this issue, either use a non-zero step size, or remove the step size altogether (so that the default step is used).
Continue readingFix “LIMIT is only supported in combination with either BYSCORE or BYLEX” in Redis
If you’re getting an error that reads “LIMIT is only supported in combination with either BYSCORE or BYLEX” it’s probably because you’re trying to use the LIMIT
clause without using the BYSCORE
or BYLEX
arguments.
This can happen when using the VRANGE
command without either of the BYSCORE
or BYLEX
arguments.
To fix this issue, use either the BYSCORE
or BYLEX
argument when using the command. This obviously means that we need to adjust our query so that it’s querying by score or lexicographically.
Fix Error 6358 “…is not a valid style number when converting to XML” in SQL Server
If you’re getting error msg 6358 which reads something like 300 is not a valid style number when converting to XML, it’s probably because you’re trying to convert a value to XML, but the style that you’re specifying isn’t supported for conversions to that data type.
It’s not that the conversion can’t happen, it’s just that it can’t happen using the style that you’re specifying.
Continue readingFix “WRONGTYPE Operation against a key holding the wrong kind of value” when using ZCOUNT in Redis
If you get an error that reads “WRONGTYPE Operation against a key holding the wrong kind of value” when using the ZCOUNT
command in Redis, it’s probably because you’re passing a key with the wrong data type.
To fix this issue, be sure that the key you pass to the ZCOUNT
command holds a sorted set.
Fix Error Msg 6855 “Inline schema is not supported with FOR XML PATH” in SQL Server
If you’re getting error Msg 6855 in SQL Server that reads “Inline schema is not supported with FOR XML PATH“, it’s because you’re trying to add an inline schema to an XML document that you’re generating using PATH
mode with the FOR XML
clause.
As the message alludes to, PATH
mode doesn’t support the ability to create an inline schema when using the FOR XML
clause.
To fix this issue, either use a different mode to generate the XML with an inline schema (specifically, use either AUTO
or RAW
mode), or don’t generate an inline schema at all.