postgresql-9.2

I installed postgresql on mac using brew. I wasn't asked about for the password for postgresql during the installation. Now I need to create a user and can't: Alexs-MacBook-Air:mydir alex$ su - postgres Password: su: Sorry Whatever password (including empty) I use, it is wrong. What's the easiest way to reset it? Craig Ringer You're trying to access the system user named postgres . According to comments you left on the other answers, there is no such user. You can't change the password of a user that doesn't exist. Perhaps it's _postgres or postgres_ ? I know some installers on OS X use weird

Is there any command to find all the databases size in Postgres? I am able to find the size of a specific database by using following command: select pg_database_size('databaseName'); And... If in case you may not want to type a whole query... you can also type... \l+ <database_name> and you will get some details about the database, including the size of the database. And... To get sizes of all databases. you can just type... \l+ You may need to go into the postgresql command prompt to query with these postgresql helper commands. Check other postgresql helper commands by typing \? at the

I have the following query: SELECT field FROM myTable WHERE field ~ '\\Qprefix[\\E.+' It won't find values like prefix[foo] . How can I replace \Q..\E ? This form of regex with a \Q..\E unquoted substring is only supported by PCRE , which is not available natively in PostgreSQL. If your program must deal with this syntax in general, the PCRE support can be installed as an extension, as provided here: https://github.com/petere/pgpcre On the other hand, if it's only that one regex that should be made to work, first note that the double backslashes in '\\Qprefix[\\E.+' means literally two

Is it possible to cancel previous operations in a user defined function? For example: CREATE OR REPLACE FUNCTION transact_test () RETURNS BOOLEAN AS $$ BEGIN UPDATE table1 SET ... UPDATE table2 SET ... IF some_condition THEN --Here is possible to cancel all above operations? RETURN FALSE; END IF; RETURN TRUE; END; $$ LANGUAGE plpgsql; Both answers so far are incorrect. If you try to start a transaction or use a SAVEPOINT inside a plpgsql function you get an error message like this: ERROR: cannot begin/end transactions in PL/pgSQL HINT: Use a BEGIN block with an EXCEPTION clause instead.

I am working on a perl script, where i need to run update queries. But I need to check if the update sql command does not violate unique key constraint. So if I have a table tb(C1,C2,C3) and my update query is like: update tb set C1='b1' where C2='a1' ; Is there a way to find if a unique key constraint exist for column C1,C2 before trying to update? Ie: UNIQUE(C1,C2) . You can query the system catalogs for unique constraints , in particular pg_constraint and pg_attribute : SELECT c.conname, pg_get_constraintdef(c.oid) FROM pg_constraint c JOIN ( SELECT array_agg(attnum::int) AS attkey FROM pg

I am having trouble updating multiple columns properly with rails activerecords. I want to use something like update which basically gets updated_at updated, but i just cant pass multiple column. I could use update_all but it doesnt update updated_at with the current timestamp. Here's what i'ved tried: this doesnt work: (only takes in payment_total but not the rest) retval = @invoice.update(:payment_total => 20, :due_amount => 10, :data => clonedata.to_json) :data - this is actually a json field output: nothing this works: retval = Invoice.where(:id => @invoice.id).update_all(:payment_total =>