mysql show tables concat comma delimited

#Mysql show tables concat comma delimited how to

The following shows the syntax of the GROUP_CONCAT() function: GROUP_CONCAT(expression )Ĭode language: SQL (Structured Query Language) ( sql )

The GROUP_CONCAT() function is an aggregate function that concatenates all non-null values in a column. Introduction to SQLite GROUP_CONCAT() function

#Mysql show tables concat comma delimited how to

However, note that the effective maximum length of the return value is itself constrained by the value of max_allowed_packet.Summary: in this tutorial, you will learn how to use the SQLite GROUP_CONCAT() function to concatenate non-null values in a column. This variable’s value can be set higher, by using the following syntax: SET group_concat_max_len = val One important thing you need to be aware of when using GROUP_CONCAT() is that the result is truncated to the maximum length that is provided by the group_concat_max_len system variable, which has a default value of 1024. | Tom Jones | Long Lost Suitcase,Praise and Blame,Along Came Jones | | Michael Learns to Rock | Eternity,Scandinavia,Blue Night | | Iron Maiden | Somewhere in Time,Piece of Mind,Powerslave,Killers,No Prayer for the Dying | | Devin Townsend | Epicloud,Ziltoid the Omniscient,Casualties of Cool | | Allan Holdsworth | All Night Wrong,The Sixteen Men of Tain | | ArtistName | GROUP_CONCAT(al.AlbumName) | We can do this thanks to the GROUP_CONCAT() function. If an artist has more than one album, all albums are displayed in a single field within a comma separated list. We could modify this query so that each artist is only listed once. | Allan Holdsworth | The Sixteen Men of Tain |Īs you can see, when using this format, if an artist has more than one album, that artist is listed out multiple times – once for each album. | The Script | No Sound Without Silence | | Iron Maiden | No Prayer for the Dying | | Devin Townsend | Ziltoid the Omniscient | So a regular query joining both tables might look something like this: USE Music For every artist, there could be many albums. There is a one to many relationship between these tables. To demonstrate this, say we have a database with two tables Artists and Albums. The GROUP_CONCAT() function can be useful for occasions where you want to provide a list of results, grouped by another column.įor example, you might want a list of artists, with each artist followed by a list of albums they’ve released. We also use the SEPARATOR argument to specify that the delimiter to be used between each (concatenated) row should be a space (instead of the default comma). In this example we return both the TaskId column and the TaskName column, separated by a closing parentheses and a space.

| 1) Do garden 2) Feed cats 3) Paint roof 4) Take dog for walk 5) Relax 6) Feed cats | | GROUP_CONCAT(TaskId, ') ', TaskName SEPARATOR ' ') | You can also concatenate columns, and provide their own separator by providing a string literal value.Įxample: SELECT GROUP_CONCAT(TaskId, ') ', TaskName SEPARATOR ' ') | Do garden + Feed cats + Paint roof + Relax + Take dog for walk |

| GROUP_CONCAT(DISTINCT TaskName SEPARATOR ' + ') | To do this, use SEPARATOR followed by the string literal value that should be inserted between group values.Įxample: SELECT GROUP_CONCAT(DISTINCT TaskName SEPARATOR ' + ') However, you can specify a delimiter of your choice if required. Example – Specify a Delimiterīy default, the list is a comma-separated list. The alternative (and default) value is ASC for ascending. So in this case I use DESC to specify that it should be in descending order. | Take dog for walk,Relax,Paint roof,Feed cats,Do garden | | GROUP_CONCAT(DISTINCT TaskName ORDER BY TaskName DESC) | You can use ORDER BY to order the results by a given column.Įxample: SELECT GROUP_CONCAT(DISTINCT TaskName ORDER BY TaskName DESC) So in this case, “Feed cats” is only listed once, whereas it was listed twice in the previous example. | Do garden,Feed cats,Paint roof,Relax,Take dog for walk | You can use DISTINCT to remove duplicates (so that duplicate records become one record).Įxample: SELECT GROUP_CONCAT(DISTINCT TaskName) Note that there are restrictions on how long this list can be. By default, the list is separated by a comma. | Do garden,Feed cats,Paint roof,Take dog for walk,Relax,Feed cats |Īs you can see, each row from the result set has been concatenated into a single row. Here’s a basic example to demonstrate the GROUP_CONCAT() function: SELECT GROUP_CONCAT(TaskName) The Dataįirst, let’s use the following data in our first few examples: USE Solutions This article provides examples of how it all works. The GROUP_CONCAT() function was built specifically for the purpose of concatenating a query’s result set into a list separated by either a comma, or a delimiter of your choice. In MySQL, you can return your query results as a comma separated list by using the GROUP_CONCAT() function.