![]() ![]() Is the a way to "officially" convert it like C's atoi? If I do this: ".ORDER BY (field+1)" I can workaround this, because somehow the string is internally being converted to integer. Sqlite> SELECT * FROM T ORDER BY CAST(value AS INTEGER) Sqlite> INSERT INTO T (value) VALUES ('03') Sqlite> INSERT INTO T (value) VALUES ('02') Sqlite> INSERT INTO T (value) VALUES ('01') Sqlite> INSERT INTO T (value) VALUES ('12') Sqlite> INSERT INTO T (value) VALUES ('11') Sqlite> INSERT INTO T (value) VALUES ('10') sqlite> CREATE TABLE T (value VARCHAR(2)) In this tutorial, you have learned how to use some techniques to perform natural sorting in MySQL.You can use CAST to cast the expression to an Integer. Some languages support natural sorting function e.g., PHP provides the natsort() function that sorts an array using natural sorting algorithm. You need to perform natural sorting in the application layer. In case, all the above solutions didn’t work for you. ![]() ORDER BY LENGTH(item_no), item_no Code language: SQL (Structured Query Language) ( sql ) The idea is to sort the item_no data by length first and then by column value as the following query: SELECT Notice that LENGTH function returns the length of a string. To achieve this result, we can use the LENGTH function. The expected result after sorting is as follows: ( 'A-30') Code language: SQL (Structured Query Language) ( sql ) Let’s take a look at another common set of data that we often have to deal with. Second, we use the ORDER BY clause to sort the rows numerically first and alphabetically then. In this query, first, we convert item_no data into an unsigned integer using the type cast. ORDER BY CAST(item_no AS UNSIGNED), item_no Code language: SQL (Structured Query Language) ( sql ) If the item_no data is in fairly standard format, you can use the following query to perform natural sorting without changing the table structure. In addition, we have to combine two columns into one when we select the data. The disadvantage of this solution is that we have to break the item_no into two parts before inserting or updating it. The query first sorts data numerically and then sorts the data alphabetically. Prefix, suffix Code language: SQL (Structured Query Language) ( sql ) Then, we can sort the data based on these columns as shown in the following query: SELECT CONCAT(prefix, suffix) The prefix column stores the number part of the item_no and suffix column stores the alphabetical part. To work around this, first we split the item_no column into 2 columns: prefix and suffix. The ORDER BY clause sorts strings in a linear fashion i.e., one character a time, starting from the first character. ![]() Unfortunately, MySQL does not provide any built-in natural sorting syntax or function. We expect to see the result like the following picture: ORDER BY item_no Code language: SQL (Structured Query Language) ( sql ) Third, query data from the items table sorted by the item_no: SELECT ( '20D') Code language: SQL (Structured Query Language) ( sql ) Second, insert some rows into the items table: INSERT INTO items(item_no) ) Code language: SQL (Structured Query Language) ( sql ) Setting up a sample tableįirst, create a new table named items by using the following CREATE TABLE statement: CREATE TABLE items ( Summary: in this tutorial, you will learn about some natural sorting techniques in MySQL using the ORDER BY clause. ![]()
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