If the value's type is boolean, you can simply use ORDER BY "isSubscribed" IS TRUE DESC. Similar to the effect of the method using the COALESCE function, in some cases, you may want to make the NULL value have the same order with some default value. Because it treats NULL and the default value in the same order, while in other methods, the null value always has a strictly higher or lower value than any other value. Note: This workaround is very different for all the above-mentioned ways, it is even different from the NULLS LAST/FIRST clause. With COALESCE, you can provide a default value if the sorted expression is NULL.įor example, ORDER BY COALESCE(cnt, 0) DESC. , val_n) returns the first non-null value. Use COALESCE functionĬOALESCE(val_1, val_2. For boolean values, True/False is equivalent to 1/0, respectively when sorting. Note: cnt IS NULL is simply a boolean value. Use multiple sorts to sort the NULL value first.įor example, ORDER BY cnt IS NULL DESC, cnt DESC. The trick: minus of NULL is still a NULL, NOT of NULl is still a NULL.įor values of types that can be applied with the reverse operator such as number, date, or boolean, reserving the order (DESC to ASC, vice versa), and adding the reverse operator to the sorted value swap NULL values' order.įor example, change ORDER BY cnt ASC to ORDER BY -cnt DESC.Ĭhange ORDER BY "isSubscribed" DESC to ORDER BY NOT "isSubscribed" ASC. There are various ways to achieve the required sorting order. Note: currently, MySQL, SQL Server do not support this feature. NULLS FIRST/LAST specifies the order of NULL values regardless of the sorting order.įor example: with ORDER BY "subscribedAt" ASC NULLS FIRST/ ORDER BY "subscribedAt" DESC NULLS FIRST, record with subscribedAt being NULL always come first. PostgreSQL, Oracle, SQLite support modifying the order of the NULL value in the ORDER BY clause by adding NULLS FIRST/LAST to the order by clause. SQL Server document: Null values are treated as the lowest possible values. MySQL document: When doing an ORDER BY, NULL values are presented first if you do ORDER BY. SQLite document: SQLite considers NULL values to be smaller than any other values for sorting purposes ![]() ![]() Oracle document: (search for the following paragraph) If the null ordering is not specified then the handling of the null values is: By default, null values sort as if larger than any non-null value ![]() In contrast, these SQL dialects treat the NULL value as smallest (the first value in ascending order of any value type): SQLite, MySQL, SQL Server. The following SQL dialects consider NULL as the largest value (the last position in ascending order of any value type): PostgreSQL, Oracle. This article explains the order of the NULL value in the ORDER BY clause in sql, with reference to the official document for each dialect.
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