In this case, simply prepending/appending the separator next to implode() is not enough, so I made this little helper function. Sometimes it's necessary to add a string not just between the items, but before or after too, and proper handling of zero items is also needed. To concatenate two or more quoted string values, you place the string next to each other as the following syntax: SELECT 'MySQL ' 'String ' 'Concatenation' Code language: SQL (Structured Query Language) (sql) Try It Out MySQL string concatenation is cleaner in comparison with other database management systems. Mysql> SELECT 1.Getting Started Introduction A simple tutorial Language Reference Basic syntax Types Variables Constants Expressions Operators Control Structures Functions Classes and Objects Namespaces Enumerations Errors Exceptions Fibers Generators Attributes References Explained Predefined Variables Predefined Exceptions Predefined Interfaces and Classes Predefined Attributes Context options and parameters Supported Protocols and Wrappers Security Introduction General considerations Installed as CGI binary Installed as an Apache module Session Security Filesystem Security Database Security Error Reporting User Submitted Data Hiding PHP Keeping Current Features HTTP authentication with PHP Cookies Sessions Dealing with XForms Handling file uploads Using remote files Connection handling Persistent Database Connections Command line usage Garbage Collection DTrace Dynamic Tracing Function Reference Affecting PHP's Behaviour Audio Formats Manipulation Authentication Services Command Line Specific Extensions Compression and Archive Extensions Cryptography Extensions Database Extensions Date and Time Related Extensions File System Related Extensions Human Language and Character Encoding Support Image Processing and Generation Mail Related Extensions Mathematical Extensions Non-Text MIME Output Process Control Extensions Other Basic Extensions Other Services Search Engine Extensions Server Specific Extensions Session Extensions Text Processing Variable and Type Related Extensions Web Services Windows Only Extensions XML Manipulation GUI Extensions Keyboard Shortcuts ? This help j Next menu item k Previous menu item g p Previous man page g n Next man page G Scroll to bottom g g Scroll to top g h Goto homepage g s Goto search > REPLACE(tags,', ',''' subtag UNION SELECT '''),''') A') INTO FROM (select GROUP_CONCAT(tag separator ', ') tags FROM fruit) A Here is the output mysql> SELECT CONCAT('SELECT GROUP_CONCAT(subtag) fruits FROM (SELECT ''', However, when I join that view to another table, I am now getting duplicates. In the first view, I am using groupconcat( distinct.) and when I run that view by itself, I can see only the distinct values as expected. SELECT s FROM EXECUTE s DEALLOCATE PREPARE s I have one view that gives me comma separated values and want to use that data in another view. Returns the comma-separated list of quoted schema names where user-defined functions are searched when they are referenced without the schema name. REPLACE(tags,', ',''' subtag UNION SELECT '''),''') A') INTO (select GROUP_CONCAT(tag separator ', ') tags FROM fruit) A Here is the code SELECT CONCAT('SELECT GROUP_CONCAT(subtag) fruits FROM (SELECT ''', Here is the query: SELECT projects.projID, projects.createdBy, projects.createdOn, projects.projName, projects.projDesc, ( SELECT CONCAT (users.fname,' ',users.lname) FROM users,projassignment WHERE erName erName ) AS assignedTo FROM projects,admin,users LEFT JOIN projassignment ON projects.projID projassignment. Here are the contents now mysql> select tag from fruit Here's an example of how to use FINDINSET () to join two tables: SELECT FROM table1 INNER JOIN table2 ON FINDINSET (table1.id, table2. This function searches for a value within a comma-separated list. > ('apples, oranges'),('apples, pears'),('figs, oranges') To join two tables using a comma-separated list in the join field, you can use the FINDINSET () function in MySQL. I reloaded the data like this first: mysql> use test The only way to use the view is to do this convoluted solution The GROUP_CONCAT function is for query aggregation, not set manipulation. You should be storing the fruits as separate fields. Please note that each tag field (holding two fruits) is unique. Mysql> select group_concat(distinct tag) tag from fruit Īccording the info you just added to the question, each tag has two fruits. We actually have tables like that, but the csv columns are meant to be human readable and not ever used for joining. used to denormalize rows into a string of comma-separated values (CSV) or. Note the output of these queries mysql> select tag from fruit The listagg function transforms values from a group of rows into a list of. > id int not null auto_increment primary key, Query OK, 0 rows affected, 1 warning (0.00 sec) I entered that data like this mysql> use test
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