The ORDER BY clause is commonly used in SQL to sort the results of a query.
It allows you to specify the order in which the results are returned.
You can specify whether the results are sorted in ascending order or descending order. You can also specify multiple columns for sorting.
Continue readingThere are four transaction modes in SQL Server. One of these is implicit mode.
In SQL Server, an implicit transaction is when a new transaction is implicitly started when the prior transaction completes, but each transaction is explicitly completed with a COMMIT or ROLLBACK statement.
This is not to be confused with autocommit mode, where the transaction is started and ended implicitly.
Continue readingIn SQL, transactions are used to maintain data integrity by ensuring that a sequence of SQL statements execute completely or not at all.
Transactions manage sequences of SQL statements that must be executed as a single unit of work, so that the database never contains the results of partial operations.
When a transaction makes multiple changes to the database, either all the changes succeed when the transaction is committed, or all the changes are undone when the transaction is rolled back.
Continue readingSQL Server error Msg 245, Level 16 tells us that there was a problem when trying to convert a value to a specific data type.
You’ll get this error if you try to insert the wrong data type into a column.
To fix this issue, make sure the data type of the value you’re trying to insert, matches the column’s type.
Continue readingIf you’ve previously created a partitioned table in SQL Server, and you now want to know how many rows are being stored in each partition, here are three queries you can use.
In particular, you can:
sys.dm_db_partition_stats viewsys.partitions view$PARTITION function in a queryBelow are examples of all three.
Continue readingIn SQL, the greater than operator (>) compares two expressions and returns TRUE if the left operand has a value higher than the right operand; otherwise, it returns FALSE.
In SQL, the greater than or equal to operator (>=) compares two expressions and returns TRUE if the left operand has a value greater than or equal to the right operand; otherwise, it returns FALSE.
In SQL, the less than or equal to operator (<=) compares two expressions and returns TRUE if the left operand has a value lower than or equal to the right operand; otherwise, the result is FALSE.
You can use it to determine whether a value is less than or equal to another value.
Continue readingIn SQL, the less than operator (<) compares two expressions and returns TRUE if the left operand has a value lower than the right operand; otherwise, the result is FALSE.
In SQL, the not equal to operator (<>) compares the non-equality of two expressions. That is, it tests whether one expression is not equal to another expression.
If either or both operands are NULL, NULL is returned.
SQL also has another not equal to operator (!=), which does the same thing. Which one you use may depend on your DBMS, which one you’re the most comfortable using, and perhaps also whether your organisation has any coding conventions that dictate which one should be used.