![]() ![]() This gives the shopkeeper the desired result so that he can begin his audit:Ĭopying data with INSERT INTO can also be done with conditions. In order to copy data from all the tables, the shopkeeper can use UNION to merge the tables together in the subquery: This query uses a subquery to find all values in âhardwareâ and then adds them to the âmasterlistâ. For example to copy all items from the table âhardwareâ to the table âmasterlistâ the following query can be run: When using INSERT INTO with the VALUES command it is possible to add entries by hand, however a query can also be used in place of the VALUES command. It is often used to insert single values into tables by running the command as such: This command inserts specified values into a specified table. This can be done using the INSERT command. Now that the shopkeeperâs master list has been created and structured, the data needs to be inserted into the table. With this done, the shopkeeper now has the following tables: The shopkeeper can use this to create his master list: Once filled out, this command will create a new table with the same table structure, but without any data. This indeed is the usage found in ECPG (see Chapter 36) and PL/pgSQL (see Chapter 43).The PostgreSQL usage of SELECT INTO to represent table creation is historical. Something like: insert into select col1, col2, col3 from Can someone give me an example or tell me what commands to use What I have so far: lconnectstr 'hostaddr192.168.10.21 port5432 dbnamedb1 userpostgres passwordtest' perform public.dblinkconnect ('con1', lconnectstr).The easiest way to create a table with the same table structure as a different table is to use:ĬREATE TABLE AS TABLE WITH NO DATA The SQL standard uses SELECT INTO to represent selecting values into scalar variables of a host program, rather than creating a new table. The master list needs to have the same table structure (columns, data-types, etc.). The shopkeeper needs to first make a new table to contain the data. You can extend your format to as many tables as needed. In order to create a master list that contains all of the storeâs items and prices the shopkeeper needs to create the table for all items and copy the data from each of the departments into the new table. However the data he needs exist in separate tables containing the inventories of each department: Take for example a shopkeeper who needs to create a master list of all the items in his store to conduct a store-wide audit. It can be used to update an inventory, create a table that has different permissions than the original, and much more. INSERT INTO SELECT FROM WHERE Ĭopying data between tables is just as easy as querying data however it will take a bit longer to run than a normal query. ![]()
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