![]() ![]() In this example, the second exit statement terminates the outer loop when j is greater than 3. NOTICE: (i,j): (1,3) Code language: HTTP ( http ) The following example places the label of the outer loop in the second exit statement: do It is the reason you see that j is 1, 2, and 3 for each iteration of the outer loop. The second exit statement terminates the inner loop when j is greater than 3. ![]() That’s why you see the value of i in the output is 1, 2, and 3. The first exit statement terminates the outer loop when i is greater than 3. Since both exit statements don’t use any loop labels, they will terminate the current loop. This example contains two loops: outer and inner loops. NOTICE: (i,j): (3,3) Code language: HTTP ( http ) The following example illustrates how to use the exit statement in unconditional loops: do 1) Using PL/pgSQL Exit statement to terminate an unconditional loop Let’s take some examples of using the PL/pgSQL exit statement. some more code END block_label Code language: CSS ( css ) PL/pgSQL Exit examples In this case, the control is passed to the statement after the end keyword of the current block: >īEGIN - some code EXIT In addition to terminating a loop, you can use the exit statement to terminate a block specified by the begin.end keywords. The exit when is definitely cleaner and shorter. The following statements are equivalent: exit when counter > 10 Code language: PHP ( php ) if counter > 10 then The exit statement will terminate the loop if the boolean_expression evaluates to true. The when boolean_expression clause is used to specify a condition that terminates a loop. If you don’t use the label, the exit statement will terminate the current loop. Depending on the label, the exit statement will terminate the corresponding loop. The label is the loop label of the current loop where the exit is in or the loop label of the outer loop. The following shows the syntax of the exit statement: exit Code language: CSS ( css ) The exit statement allows you to terminate a loop including an unconditional loop, a while loop, and a for loop. Introduction to the PL/pgSQL Exit statement One further advantage of the separate schemas is that, in theory, we could at any time start using completely separate databases, one for each customer or just one additional for a much larger customer that's eating up all resources on the DB.Summary: in this tutorial, you will learn about the exit statement and how to use it to terminate a loop or a block. Migrations take longer as there are more objects to touch. Adding a new customer requires `pg_dump` to be present as it dumps the public schema (the blueprint), creates a new schema, and loads the dump into that schema. Number of objects (tables, indexes, sequences) is multiplied by number of customers. It's almost impossible to have a bug causing data to spill from one customer to the other, which is quite high chance when you always have to remember to load data through the current customer. Instead of `current_(params)` you can now simply do `Post.find(params)`. You just activate the right customer (e.g. At the beginning of the session you choose which customer you want to operate on. No customer_id column in any table you have to remember setting in your WHERE clause. When you enter a psql session, you `SET search_path TO customer ` and that's it. As with any technique, there's pros and cons. ![]() The other way around, lots of customers with little data would not scale, I'd say. I guess it works well if you have a small number of customers, each with lots of data. We use the apartment gem pjungwir mentioned. Nowarning (\w) Don't show warnings after every statement.įor server side help, type 'help contents' Warnings (\W) Show warnings after every statement. Might be needed for processing binlog with multi-byte charsets. Takes database name as argument.Ĭharset (\C) Switch to another charset. System (\!) Execute a system shell command. Status (\s) Get status information from the server. Nopager (\n) Disable pager, print to stdout. Optional arguments are db and host.Įgo (\G) Send command to mysql server, display result vertically. ![]() Note that all text commands must be first on line and end with ' 'Ĭlear (\c) Clear the current input statement.Ĭonnect (\r) Reconnect to the server. ![]()
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