sql - Substring in postgres -


i have 2 tables in postgres trying compare , having trouble accessing substring 1 , comparing one. i'm new postgres (specifically sql through pgadmin), suggestions helpful.

i trying count number of id numbers similar between 2 tables, 1 set of numbers longer other due concatenated fips code. don't want trim data if don't have to, right have:

select count(id_a) server.table1  where(id_a not null  , id_a in (select (substring(id_b 3 8) server.table 2)))

i answer because little catch on query. if typo delete after update original question.

select count(id_a)    server.table1  (     id_a not null          , id_a in (select (substring(id_b 3 8)                          server.table2)                      )                    ^        )                                  |_ parenthesis in wrong place

note either missing parenthesis or excessive one.

the right query be:

select count(id_a)    server.table1  id_a not null    , id_a in (select substring(id_b 3 8)                    server.table2)

as @ziggycrueltyfreezeitgeister pointed out, don't need id_a not null if don't have null values on it.


-

Popular posts from this blog

Apache NiFi ExecuteScript: Groovy script to replace Json values via a mapping file -

i working apache nifi 0.5.1 on groovy script replace incoming json values ones contained in mapping file. mapping file looks (it simple .txt): header1;header2;header3 a;some text;a2 i have started following: import groovy.json.jsonbuilder import groovy.json.jsonslurper import java.nio.charset.standardcharsets def flowfile = session.get(); if (flowfile == null) { return; } flowfile = session.write(flowfile, { inputstream, outputstream -> def content = """ { "field1": "a" "field2": "a", "field3": "a" }""" def slurped = new jsonslurper().parsetext(content) def builder = new jsonbuilder(slurped) builder.content.field1 = "a" builder.content.field2 = "some text" builder.content.field3 = "a2" outputstream.write(builder.toprettystring().ge...
Read more

node.js - How do I prevent MongoDB replica set from querying the primary? -

read-operations-only: is there way have mongodb replica set, make mongodb instance on box connected to, mongodb gets queried? i have 3 ec2 instances behind aws load balancer. on each ec2 instance runs mongodb, part of replica set. i have express endpoints on nodejs , connect replica set follows mongodb.mongoclient.connect('mongodb://1.1.1.1,2.2.2.2,3.3.3.3.', function (err, db) { if (err) { complete('{}'); } else { i distribute load of queries evenly across 3 instances of mongodb replica set instead of default having queries routed ec2 instance primary mongodb defined, because destroys point of load balancer (which balance load of queries across 3 instances evenly). my understanding when connecting mongodb replica set, primary instance selected unless primary instance down, , therefore purpose of every secondary instance serve backup. in example people call hot,cold,cold. because there 2...
Read more