The NULLS FIRST option specifies that the NULLs will appear at the beginning of the result set while the NULLS LAST option place NULLs at the end of the result set. SQLite 3.30.0 added the NULLS FIRST and NULLS LAST options to the ORDER BY clause. It means that NULLs will appear at the beginning of the result set if you use ASC or at the end of the result set when you use DESC. When it comes to sorting, SQLite considers NULL to be smaller than any other value. NULL is even cannot be compared with itself NULL is not equal to itself so NULL = NULL always results in false. Simply put, if the two pieces of information are unknown, you cannot compare them. NULL is special because you cannot compare it with another value. Instead of using a special value to indicate that the information is missing, NULL is used. However, both of these values do not clearly show that the birthday is unknown. To represent the unknown birthday information in the database, you may use a special date like or an '' empty string. At the time of saving the artist’s record, you don’t have the birthday information. Suppose you want to store the birthday of an artist in a table. It denotes that the information missing or the data is not applicable. The number 3 and 2 refers to the AlbumId and Milliseconds in the column list that appears in the SELECT clause. ORDER BY 3, 2 Code language: SQL (Structured Query Language) ( sql ) Instead of specifying the names of columns, you can use the column’s position in the ORDER BY clause.įor example, the following statement sorts the tracks by both albumid (3rd column) and milliseconds (2nd column) in ascending order. If you look at the tracks of the album with AlbumId 1, you find that the order of tracks changes between the two statements. Then, it sorts the sorted result set by the Milliseconds column in descending order. SQLite sorts rows by AlbumId column in ascending order first. Milliseconds DESC Code language: SQL (Structured Query Language) ( sql ) In this case, you need to add the Milliseconds column to the ORDER BY clause as follows: SELECT name, Suppose you want to sort the sorted result (by AlbumId) above by the Milliseconds column in descending order. SQLite uses ASC by default so you can omit it in the above statement as follows: SELECT The result set now is sorted by the AlbumId column in ascending order as shown in the screenshot. Suppose you want to sort the result set based on AlbumId column in ascending order, you use the following statement: SELECT name,Īlbumid ASC Code language: SQL (Structured Query Language) ( sql ) The SELECT statement that does not use ORDER BY clause returns a result set that is not in any order. Tracks Code language: SQL (Structured Query Language) ( sql ) Suppose, you want to get data from name, milliseconds, and album id columns, you use the following statement: SELECT name, Let’s take the tracks table in the sample database for the demonstration. You can sort the result set using a column that does not appear in the select list of the SELECT clause. Then, it sorts the sorted rows using the second column, and so on. In other words, the ORDER BY clause sorts the rows using the first column in the list. The ORDER BY clause sorts rows using columns or expressions from left to right. In case you want to sort the result set by multiple columns, you use a comma (,) to separate two columns. In other words, it sorts the result set in the ascending order by default. If you don’t specify the ASC or DESC keyword, SQLite sorts the result set using the ASC option. In this syntax, you place the column name by which you want to sort after the ORDER BY clause followed by the ASC or DESC keyword. It allows you to sort the result set based on one or more columns in ascending or descending order. The ORDER BY clause comes after the FROM clause. To sort the result set, you add the ORDER BY clause to the SELECT statement as follows: SELECTĬolumn_2 DESC Code language: SQL (Structured Query Language) ( sql ) If you use the SELECT statement to query data from a table, the order of rows in the result set is unspecified. It means that the rows in the table may or may not be in the order that they were inserted. SQLite stores data in the tables in an unspecified order. Summary: in this tutorial, you will learn how to sort a result set of a query using SQLite ORDER BY clause.
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