LEFT JOIN pg_namespace N ON (N.oid = C.relnamespace) The third way is to note that the system ANALYZE command, which is executed by the autovacuum process regularly as of PostgreSQL 8.3 to update table statistics, also computes a row estimate. That can also show you how many rows are dead, which is itself an interesting number to monitor. This value can be off by a bit under heavy activity, but is generally a good estimate: SELECT schemaname,relname,n_live_tup The second approach notes that the statistics collector tracks roughly how many rows are "live" (not deleted or obsoleted by later updates) at any time. (xpath('/row/c/text()', query_to_xml(format('select count(*) as c from %I.%I', table_schema, TABLE_NAME), FALSE, TRUE, '')))::text::int AS rows_n You could automate this to run against every table in the database, but you probably don't need that level of accuracy or want to wait that long. You're getting a count of what that transaction sees at the point in time when it executes. This is because PostgreSQL keeps row visibility information in the row itself, not anywhere else, so any accurate count can only be relative to some transaction. If you want a true count, you have to execute the SELECT statement like the one you used against each table. There's three ways to get this sort of count, each with their own tradeoffs. MySQL CONCAT returns NULL if any field contain NULL.Fastest Way to Find Distance Between Two Lat/Long Points.MySQL Data - Best way to implement paging?.Access Denied for User (using password: YES) - No Privileges?.How to change the default collation of a table?.SQL select only rows with max value on a column.How to test if a string is JSON or not?.What's the difference between utf8_general_ci and utf8_unicode_ci?. ![]() How do I manage MongoDB connections in a Node.js web application?.How to configure MongoDB Java driver MongoOptions for production use?.How to start a mongodb shell in docker container?.Mongoose and multiple database in single node.js project.Get the _id of inserted document in Mongo database in NodeJS.Meteor app - resetting a deployed app's DB.MongoDB: exception in initAndListen: 20 Attempted to create a lock file on a read-only directory: /data/db, terminating. ![]() How to remove array element in mongodb?.PostgreSQL array of elements that each are a foreign key.Backup/Restore a dockerized PostgreSQL database.Adding comment to column when I create table in PostgreSQL?.Fastest check if row exists in PostgreSQL.How to create User/Database in script for Docker Postgres.SQL update fields of one table from fields of another one.Skipping acquire of configured file 'main/binary-i386/Packages'. ![]()
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