Let us now see an example where these conditions are most often used, that is, using query results for condition specification. It will be as follows when variable1 and variable2 have 98 and 100 values, respectively. RAISE NOTICE 'variable1 is greater than b' įirstly, variable1 is greater than variable2 condition will be checked and if not then it will go to else if block, where less than condition will be checked and if both conditions evaluate to false then message with a notice saying both are equal, will be raised. Now, we will use format3 to implement the same use case scenario as of example1 and example2 and apply the most compact and appropriate solution for this use case of number comparison. This problem is overcome using the format3 of if-else, where we can do nesting of other if-else or if statements inside the original ones up to any level as per our convenience. Even when both the variables are equal, then the message will be displayed saying variable1 is not greater than variable2, which means it can be small or equal.
RAISE NOTICE 'variable1 is not greater than variable2' Īs we can see, here we can’t check for the equal condition. RAISE NOTICE 'variable1 is greater than variable2' RAISE NOTICE 'variable1 is greater than variable2 ' Here, three separate if statements will be used to achieve our use-case requirement. In our first example, we will consider two variables and then, using the format 1 mentioned above we will write the statements in such a way that when the variable1 is less than or greater than or equal to variable2, then an appropriate message with the notice will be raised after they are compared using comparing operators. This is a completely customisable structure and can be used as per our convenience and requirement. The nesting if inside else of another if is also possible. We can use only if the statement if we want to execute certain statements on fulfilment of some condition, or we can use the second format where the control when the condition evaluates to true and when it evaluates to false is given can execute our statements accordingly. This method also works with the technique of making an export_table as demonstrated in Neto's answer.Hadoop, Data Science, Statistics & others From there you can simply copy the generated INSERT-Statements. notepad++) you get a script to create the whole table. If you open the resulting file with a text reader (e.g.Open the tab "Dump Options #2" at the bottom and check "Use Column Inserts".Select a file path to store the backup.Right click on target table and select "Backup".This is an easy and fast way to export a table to a script with pgAdmin manually without extra installations: Server, and no SQL superuser privileges are required.
This means that fileĪccessibility and privileges are those of the local user, not the Specified file, psql reads or writes the file and routes the dataīetween the server and the local file system. SQL COPY command, but instead of the server reading or writing the There is also the \copy command of psql that: If both run on the same machine, it doesn't matter much, but it does for remote connections. Import the same to another table of the same structure anywhere with: COPY other_tbl FROM '/path/to/file.csv' ĬOPY writes and read files local to the server, unlike client programs like pg_dump or psql which read and write files local to the client. You get a file with one table row per line as plain text (not INSERT commands), it's smaller and faster: COPY (SELECT * FROM nyummy.cimory WHERE city = 'tokio') TO '/path/to/file.csv'
column-inserts will dump as insert commands with column names.Īs commented below, creating a view in instead of a table will obviate the table creation whenever a new export is necessary. $ pg_dump -table=export_table -data-only -column-inserts my_database > data.sql Create a table with the set you want to export and then use the command line utility pg_dump to export to a file: create table export_table as
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