![]() ![]() True - there are many personal static web pages on the Internet working without databases, but in today's dynamic information stream static pages are archaic. Don’t forget that you can select fixed values if no column from the query has the info ( INSERT INTO X(p,c,age) SELECT personname, cityname, 23 FROM. PostgreSQL examples: Create Tables and Insert, Select, Update or Delete data PostgreSQL Databases are indispensable when it comes to contemporary web applications. ![]() The number of columns inserted to must match the number of columns selected. However, I trust that the general pattern shown first will suffice for your learning write a SELECT that shows the data you want to insert, then simply write INSERT INTO table(columns) above it. If you just want to mix every person with every city you can do: INSERT INTO employee(personname,cityname)īut be warned, two people and two cities will cause 4 rows to be inserted, and so on (20 people and 40 cities, 800 rows. Provide eg a cityname in Person (because it seems more likely that one city has many person) then you can do INSERT INTO employee(personname,cityname)īut even then, the tables are related between themselves and don’t need the third table so it’s perhaps something of an academic exercise only, not something you’d do in the real world In your case there isn’t really anything to join on because your one-column tables have no column in common. 190 I'm not sure if its standard SQL: INSERT INTO tblA (SELECT id, time FROM tblB WHERE time > 1000) What I'm looking for is: what if tblA and tblB are in different DB Servers. The general pattern for turning a select that has two base tables giving info, into an insert is: INSERT INTO table(column,list,here) How to use a SQL for loop to insert rows into database Ask Question Asked 12 years, 9 months ago Modified 5 months ago Viewed 101k times 45 I'm using Postgres, and I have a large number of rows that need to be inserted into the database, that differ only in terms of an integer that is incremented. There doesn’t appear to be any obvious relationship between city and person which will make your life hard The textbook I have for class doesn't dive into sub-queries like this and I can't find any examples similar enough to mine such that I can understand how to adapt them for this use case. Notice in the last block of code, where I'm doing an INSERT into the employee table, I don't know how to string together multiple SELECT sub-queries to get both the existing records from the person and city table such that I can create a new employee entry with attributes as such: create employee entry referencing existing records Create a employee table w/ForeignKey referenceĮname VARCHAR(255) REFERENCES person(pname) NOT NULL,Įcity VARCHAR(255) REFERENCES city(cname) NOT NULL, Create a city table + insert single row I am learning SQL (postgres) and am trying to insert a record into a table that references records from two other tables, as foreign keys.īelow is the syntax I am using for creating the tables and records: - Create a person table + insert single row ![]()
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