![]() The result may be affected by table data, random numbers or server variables.ĬONTAINS SQL: It is the default. NOT DETERMINISTIC: It means that the function may return a different result given a set of input parameters. LANGUAGE SQL: It is in the syntax for portability but will have no impact on the function.ĭETERMINISTIC: It means that the function will always return one result given a set of input parameters. IN OUT: The parameter can be referenced by the procedure and the value of the parameter can be overwritten by the procedure. OUT: The parameter can not be referenced by the procedure, but the value of the parameter can be overwritten by the procedure. The value of the parameter can not be overwritten by the procedure. IN: The parameter can be referenced by the procedure. When creating a procedure, there are three types of parameters that can be declared: Parameter: One or more parameters passed into the procedure. ![]() Procedure_name: The name to assign to this procedure in MariaDB. See this post and this GitHub repository for working code.) ] I removed the code because it was buggy triggered MariaDB bugs. So I wrote a stored procedure which does the boring work for us: Of course, having to CREATE a TABLE each time is not very comfortable, even with table discovery. Look again at the example – everything will be clear. CONNECT supports table discovery, which means that it automatically knows which columns and types are needed.Ĭonfused? I hope not. So, we can use that query in all contexts where SELECT works.Īlso note that we don’t have to specify the table structure. But since this work is done by the CONNECT engine, from the MariaDB point of view we are just querying a table. This means that, when the table is queried, the CONNECT engine opens a connection to the local server, it executes SHOW MASTER STATUS, and it returns the results of that statement. Since I specified a SRCDEF table option, the data source is not a table in the server, it is the resultset of the specified query ( SHOW MASTER STATUS). ![]() In this case I defined a table which connects to a MariaDB/MySQL server ( TABLE_TYPE=MYSQL). Supported data sources include several file formats, remote DBMS’s and more. CONNECT is a storage engine which allows the users to read data from several kind of data sources as if they were regular SQL tables. How does the trick work? If you know CONNECT, probably you already guessed. ![]() | I'll do something with binlog.00000242965 |Īs you can see, with this trick I was able to use a cursor with SHOW MASTER STATUS. | CONCAT('I''ll do something with ', v_file, v_position) | SELECT CONCAT('I''ll do something with ', v_file, v_position) SELECT `File`, `Position` FROM show_master_status I faced all these problems while developing STK/Unit and in other projects.īut MariaDB lets us workaround these limitations – and the funny thing is that probably its developers are not aware about this! Here is an example: CREATE OR REPLACE TABLE show_master_status This means that in some contexts you may have to deal to annoying resultsets, or perhaps you cannot call those procedures (within triggers or functions). ![]() However, stored procedures could return one or more resultsets too, and you cannot invoke them with DO. MariaDB and MySQL support the DO statement, which is identical to SELECT except that it doesn’t return any result. An example is CHECK TABLES: even if you don’t care about the resultset (which would be a serious limitation), you cannot execute it in a stored procedure or in a prepared statements. This means that there is no way to read the output of these statements within a stored procedure or trigger.Īlso, some statements cannot be executed in a stored procedures and/or in prepared statements.
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