Example #1: Find the order id and ordering date and time of orders, arranged in ascending order by ordering time.Įxample #2: Find the order id and shipping date of orders, arranged in ascending order by shipping date. Let us discuss examples of SQL ORDER BY DATE. Basic SQL Queries with DATE field values in ORDER BY clause Now we are all set to try a few examples based on the ORDER BY DATE clause with the help of this table.

In the shipped_at field, we have just added a few days to the current date of the system. The former is of the DATETIME data type and the latter is of the DATE data type. Note that we have two date fields, ordered_at, and shipped_at column. The data in the populated e-transactions table look something as follows: We can use the following INSERT statement for this purpose. Let’s insert a few records in it to work with. We can use the following CREATE TABLE statement to create the said table. pertaining to orders placed on an ecommerce platform. As the name suggests, the table contains details such as order date, ship date, etc. Ergo, let’s create a dummy table called “e-transactions”. In order to illustrate the working of the ORDER BY DATE statement, what can be better than trying a few examples on a dummy table. Having learned the syntax and parameters used for writing ORDER BY clauses, let us try a few examples to understand the concept in detail. ASC | DESC: Order of sorting as in ascending(ASC) or descending(DESC).date_field: Column of date data type according to which the records have to be sorted.condition_expression: Condition on the basis of which rows have to be filtered.table_name: Database table from which the above-mentioned columns have to be fetched.

column_name_1, column_name_2, …, column_name_n: columns or fields that have to be fetched for the final result set.

The parameters used in the above-mentioned syntax are as follows: The basic syntax used for writing the SELECT query with ORDER BY clause is as follows: But unless the difference in uniqueness between threadId and currentUserId is a lot, or you have a lot of data, you probably won't notice much of a difference, so either definition should be equally fine.Hadoop, Data Science, Statistics & others So if threadId is more unique of a field, you could try this index definition as well CREATE INDEX IX_YourIndexName ON message (threadId, currentUserId, timestamp). By defining your indexes with the most unique fields first, it improves the selectivity of that index because less values need to be seeked on upfront. Note you might even see a slight performance benefit by switching around the order of currentUserId and threadId in the index definition, assuming the threadId is more unique than the currentUserId in the table. For more information on indexing in SQLite. And then also adding the fields from your ORDER BY clause will help sort the index on those fields as well which will reduce the work for sorting when your query runs. The reasoning being you should index on all fields in your predicates ( JOIN, WHERE, and HAVING clauses) to create a fully covering index (see 1.7 Covering Indices) which would be the currentUserId and threadId in this case. As ypercube mentioned, you'll want to create your index on all three fields, currentUserId, threadId and timestamp like so: CREATE INDEX IX_YourIndexName ON message (currentUserId, threadId, timestamp).

Sqlite order by