Here’s a nifty trick we can use in MariaDB to return the number of days in a month based on a given date.
Continue readingAuthor: Ian
Fix “INSERT has more expressions than target columns” in PostgreSQL
If you encounter an error that reads “INSERT has more expressions than target columns” when trying to insert data in Postgres, it’s because you’re trying to insert data into more columns than the table actually contains.
Continue reading3 Ways to Get the First Day of the Month in SQL Server
Below are three options for using T-SQL to return the first day of the month in SQL Server.
This could be the first day of the current month, or the first day of a month based on a given date.
Continue readingSubtract Minutes from a Time Value in PostgreSQL
In PostgreSQL, we can use the - operator to subtract one or more minutes from a time value.
By “time” value, this could be an actual time value, a timestamp, or an interval. We can also subtract minutes from a date value or a date and time combination.
Fix “date is incompatible with int” in SQL Server when Adding to or Subtracting from a Date
If you’re getting error message “Msg 206” that reads “Operand type clash: date is incompatible with int” in SQL Server while trying to add to (or subtract from) a date, it’s probably because you’re trying to perform arithmetic between an integer and a date value.
To fix this issue, either change the date value to a datetime value or use the DATEADD() function.
How to Get Values That Don’t Contain Numbers in SQL Server
If you have a column in a SQL Server database table that contains character data, but some rows also contain numbers within that data, you can use the following technique to return just those rows that don’t contain numbers.
Numbers can be represented by words and other symbols, but for the purpose of this article, “number” means “numerical digit”. So we’re finding values that don’t contain any numerical digits.
Continue readingAdd Months to a Date in SQLite
In SQLite, we can use the DATE() function to add one or more months to a date.
When we’re dealing with datetime values, we can use the DATETIME() function.
6 Ways to Delete Duplicate Rows that have a Primary Key in SQLite
Below are six examples that delete duplicate rows from a table in SQLite when those rows have a primary key or unique identifier column.
In these instances, the primary key must be ignored when comparing duplicates (due to the fact that primary keys prevent duplicate rows by definition).
Continue readingHow to Get the Last Day of the Month in Oracle
In Oracle Database we can use the LAST_DAY() function to return the last day of a given month. This can be the last day of the current month or the last day of month based on a specified date.
How to Get the Last Day of the Month in MySQL
We can use MySQL’s LAST_DAY() function to return the last day of a given month.
This could be the last day of the current month, or the last day of the month based on a date that we specify.
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