Postgresql set variable from select. PSQL has a conditionals and variables, and the ability to .

Postgresql set variable from select In pure SQL style, I could do something like the following: // here declaring function and etc DECLARE cnt INTEGER; E This executes query and discards the result. Feb 23, 2022 · I have a function that uses set_config with is_local = true to set a variable. Oct 30, 2023 · To assign the results of a SELECT query to variables in PostgreSQL, you can use the SELECT INTO statement. Mar 15, 2016 · Declare variable for SELECT statement in Postgres function Ask Question Asked 9 years, 8 months ago Modified 9 years, 8 months ago Nov 13, 2025 · If this variable is set to an integer value greater than zero, the results of SELECT queries are fetched and displayed in groups of that many rows, rather than the default behavior of collecting the entire result set before display. Nov 13, 2025 · The SELECT list (between the key words SELECT and FROM) specifies expressions that form the output rows of the SELECT statement. The typical way to make a psql variable assignment is via use of \set. I would do this after a Jan 30, 2024 · The \set command is not part of PostgreSQL itself, but a feature of the psql command-line utility. Syntax: select select_list into variable_name from table_expression; In this syntax, one can place the variable after the into keyword. name). : DECLARE var_1 INTEGER; var_2 DATE; BEGIN select col1, col2 into var_1, var_2 from some_table However neither of that is necessary in a trigger as you can simply use the reference to the NEW record directly in the INSERT statement: Mar 19, 2024 · In this tutorial, you will learn how to use the PL/pgSQL SELECT INTO statement to select data from the database and assign it to a variable. user. *, a. The function returns and integer, the id of the row inserted. You can use it to set "customized options". PSQL has a conditionals and variables, and the ability to Jul 15, 2025 · PostgreSQL, one of the most powerful and advanced open-source relational database management systems, provides robust support for procedural programming through its PL/pgSQL language. Let us better understand Sep 4, 2020 · Addendum to the accepted answer My use case doesn't return rows. I did come across other SO posts, but none of them helped in my situation. Aug 4, 2023 · Variables in block and subblock See more Introduction to variables in PL/pgSQL A variable is a meaningful name of a memory location. variable_conflict. Variables are simply name/value pairs, where the value can be any string of any length. Feb 2, 2024 · This article teaches the reader how to create variables in PostgreSQL and use them to query the database. Nov 13, 2025 · PostgreSQL 's behavior for a set-returning function in a query's select list is almost exactly the same as if the set-returning function had been written in a LATERAL FROM -clause item instead. Mar 19, 2024 · You will learn about the PL/pgSQL record types that allow you to define variables that can hold a sinle row of a result set. I'm having issues with syntax, and honestly just understanding how to set the value from within the case statement. Sure, just use \set v3 'another value'. 3+. Jul 24, 2018 · I am new working postgresql and pgadmin4. Dec 19, 2018 · 0 -- It works! select * from device where device. In PostgreSQL, variables are declared using the DECLARE statement. Mar 14, 2023 · With MSSQL it's easy, the @ marking the start of all variable names allows the parser to know that it is a variable not a column. In the case statement I'm trying to do bitwise operation on options field CREA Jan 24, 2023 · This article covers how stored procedures can make use of variables to be more functional and useful. The target variable can be a simple variable Sep 8, 2023 · I'm trying to declare a variable for later use in a PostgreSQL query. Arrays of any built-in or user-defined base type, enum type, composite type, range type, or domain can be created. 3 Asked 10 years, 8 months ago Modified 10 years, 8 months ago Viewed 22k times Mar 11, 2021 · I want to do this inside a plpgsql function WITH set1 AS ( select * from table1 where -- reduce table1 to the small working set once for multiple reuse ), query_only_for_select_into AS There is an almost identical, but not really answered question here. user_id in (select user_id from user); -- It doesn't work! select user_id into test from user; select * from device where device. After defining PL/pgSQL, stored procedures, and variables, it provides examples of how variables can be used. To do this in PL/pgSQL, use the PERFORM statement: PERFORM query; This executes a SELECT query and discards the result. One such feature is the usage of variables, which allow you to store and manipulate values within your PostgreSQL queries. The select into statement will assign the data returned by the select clause to the variable. In 9. 1 and earlier, you also need to register a custom variable class. Sep 4, 2020 · I am trying to set a session variable in a PG SQL statement with the value from a subquery SELECT statement. This is useful for things like injecting constant values where a select is providing the input to an insert table when copying from a staging table. Before using a variable, you must declare it in the declaration section of the PL/pgSQL Nov 13, 2025 · PostgreSQL provides a number of functions that return values related to the current date and time. Understand syntax, dynamic SQL, control flow, and best practices for efficient queries. While session variables share properties with tables, their value + cannot be updated with an command. Learn how to query data from tables using SELECT statement. So, I'm needing populate the table UserRules with the result from a select on TableMix where the user name is equals to the user name on table User and the value for column <col_name> in TableMix is equals 1. Apr 1, 2021 · some_variable := 42; However to assign one or more variables from the result of a query, use select into, e. May 24, 2025 · PostgreSQL is a powerful, open-source object-relational database system that allows users to store, manage, and manipulate large datasets. In many places in code I use local variables so I would like to You'll learn about PL/pgSQL variables, and how to declare, assign, and use variables. In this article, we will provide a step-by-step guide on how to declare variables in PostgreSQL queries, along with examples and best practices. It is very powerful, available on many platforms, is installed with Postgres (often in a separate package, e. Description from the manpage: \gset [ prefix ] Sends the current query input buffer to the server and stores the query's output into psql variables (see I'm trying to set the value of a variable based on a case statement so I can use that value in the next part of my code. The already-mentioned ALTER SYSTEM command provides an SQL-accessible means of changing global defaults; it is functionally equivalent to editing postgresql. Nov 13, 2025 · An assignment of a value to a PL/pgSQL variable is written as: variable { := | = } expression; As explained previously, the expression in such a statement is evaluated by means of an SQL SELECT command sent to the main database engine. I've done this often in TSQL, but I wasn't sure about the syntax. With a table like this: create table test (id int, tags text How to use variables in psql scripts psql is a native terminal-based client for PostgreSQL. conf. Jan 8, 2015 · Assign select value to variable in PostgreSQL 9. Jun 12, 2019 · i just want to know if it is possible to declare variables on the DBeaver´s sql editor and use them on a query Aug 29, 2017 · I'm trying to set value of a variable based on case statement and return the data as a table in Postgres function. name = Users. I want to declare a variable and finally do select on my table according this variable like below: Feb 6, 2023 · Within the Advanced tab of a Resource Query, add the ability to SET sql variables before a sql command is executed. 3 If you have an older version, it's much harder to emulate this. , apt install postgresql-client-16 on Ubuntu/Debian). Conclusion In PostgreSQL, a variable is always declared with a particular data type, such as INTEGER, TEXT, DATE, TIME, etc. Sep 5, 2014 · What I need to do is set a value to a variable using the EXECUTING query. I am migrating an application from MS SQL Server to PostgreSQL. activeUserId = {{localStorage. Boost your SQL skills and streamline your database queries with expert tips and best practices. If you want to select data into variables, check out the PL/pgSQL SELECT INTO statement. How do I declare a variable for use in a PostgreSQL 8. Since the \\set command of psql can't be set dynamically, you have to fall back to runtime parameters for using dynamic variables. 4, you can accomplish the same thing by adding the parameter to your server's postgresql. PostgreSQL SELECT: Querying Data PostgreSQL SELECT: Querying Data The SELECT statement is the cornerstone of data retrieval in PostgreSQL. Unlike global configuration changes, which affect the entire PostgreSQL server and require administrative access, the SET command allows users to modify settings that are valid only for the current session. Nov 13, 2025 · PostgreSQL provides three SQL commands to establish configuration defaults. g. id%TYPE; INSERT INTO oameni VALUES (default,'lol') RETURNING id INTO myid; You also need to specify the data type of your variable; I'm glad to see postgresql supports %TYPE and %ROWTYPE. So, for example, assigning now() to a variable of type timestamp causes the variable to have the time of the current function call, not the time when the function was precompiled. If PGDATESTYLE is set in the frontend environment of a client based on libpq, libpq will automatically set DATESTYLE to the value of PGDATESTYLE during connection startup. In this article, we will explore how to use variables in PostgreSQL, including their definition, types Jun 4, 2025 · The psql command-line interface for PostgreSQL lets you pass parameters into your SQL scripts using variables. A variable holds a value that can be changed through the block. 1 PostgreSQL's client has provided this functionality with psql variables \set aintconst -333 \set arealconst -9. Mar 6, 2020 · PostgreSQL set session variable Asked 5 years, 8 months ago Modified 11 months ago Viewed 25k times By using variables, you can assign meaningful names to these values, making your code more understandable and easier to maintain. sql script: DO $$ DECLARE user_list integer[] = (select user_id from user where state = 'ACTIVE'); BEGIN CREATE CREATE MATERIALIZED VIEW accounts_with_active_users AS s Nov 10, 2012 · PostgreSQL has a limited built-in way to define (global) variables using "customized options". This statement allows you to define the name, data type, and initial value of a variable. values. Row Security Policies are a great feature Sep 5, 2019 · When developing in PostgreSQL, one may run into the fringe situation of being unable to use PL/pgSQL. There are functions to control parameters, there are functions for index maintenance, others are for recovery and or backup control and there is much more. portal left outer join a. The relevant section in the documentation includes this: psql provides variable substitution features similar to common Unix command shells. To declare a variable, use the “DECLARE var_name data_type:= expression;” syntax. SELECT $$ May 1, 2013 · SELECT INTO unsolvedNodes array_agg(DISTINCT idDestination), lengths array_agg(length) FROM road WHERE idOrigin = ANY(solvedNodes) AND NOT (idDestination = ANY(solvedNodes)); How to use only one SELECT INTO instruction to set multiple variables? Jul 9, 2015 · SET abc. Dec 28, 2024 · Learn how to declare variables in PostgreSQL using PLpgSQL. It allows you to fetch data from one or more tables in your database. The expression must yield a single value (possibly a row value, if the variable is a row or record variable). They are created and assigned in their own namespace in a session with SET. May 10, 2022 · --test @set test = good --testQ @set testQ = select date from table where id = 1; I need to store the query result, NOT the query statment, someone knows if this is Nov 13, 2025 · SET TRANSACTION SNAPSHOT can only be executed at the start of a transaction, before the first query or data-modification statement (SELECT, INSERT, DELETE, UPDATE, MERGE, FETCH, or COPY) of the transaction. conf file. This command is extremely useful for temporary adjustments or tuning parameters for specific queries […] Aug 28, 2014 · PSQL Variables Since at least version 7. So, there is no such thing as a "date variable" within this system Oct 1, 2020 · I'm relatively new to postgresql, so forgive me if this is a simple problem. Basic SELECT Syntax The simplest form of a Nov 13, 2025 · When ECPG applications exchange values between the PostgreSQL server and the C application, such as when retrieving query results from the server or executing SQL statements with input parameters, the values need to be converted between PostgreSQL data types and host language variable types (C language data types, concretely). They are particularly useful when dealing with SELECT INTO statements where the result contains multiple columns from a table or view. PostgreSQL: Declaring Variables This PostgreSQL tutorial explains how to declare variables in PostgreSQL with syntax and examples. A variable is always associated with a particular data type. In which I have written join query on multiple tables like: select a. A fundamental aspect of PL/pgSQL is the use of variables that play a crucial role in storing temporary data and facilitating complex computations within database functions and procedures. In PostgreSQL, the PL/pgSQL SELECT INTO statement helps us store the table's data into a specific variable. These parameters control various aspects of how the PostgreSQL database server operates, such as: You need to use the INTO clause in the RETURNING to set the value being returned into your variable: DECLARE myid OAMENI. May 17, 2019 · I'm storing a value in a variable featureId and then trying to use that value in my SELECT statement, but postgres seems to be taking the name literally and looking for a column called "featureid". See: User-defined variables in PostgreSQL The limitations being that the name has to be qualified (must contain a dot), and only string values (type text) are stored and returned. These SQL-standard functions all return values based on the start time of the current transaction: May 26, 2017 · Simple Session Variables Simple session variables are an extension of existing session variables (aka user-defined GUCs) to add typing, privacy, improved syntax A private variable is identified with a @ prefix. Explore syntax, examples, and use cases for effective database programming. Also, the special variable FOUND is set to true if the query produced at least one row, or false if it produced no rows. Is there a way to customize these? I saw an Jul 24, 2019 · `SELECT INTO` multiple variables in PostgreSQL Asked 6 years, 3 months ago Modified 1 year, 9 months ago Viewed 12k times Oct 31, 2024 · Learn how to effectively select from a variable in PostgreSQL with this comprehensive guide. Depending on what you want exactly there are other ways: Global, persistent constants Create simple IMMUTABLE, LANGUAGE Learn how to use the psql `SELECT INTO` command to store the results of a query into a variable. xyz = 1; SELECT pg_reload_conf(); Pre-9. portal. Jul 23, 2025 · This article will explore how to declare and use record-type variables in PostgreSQL, including practical examples with the SELECT INTO statement and FOR loop. May 28, 2023 · For this, we have multiple apporaches: you can pass variables as arguments to psql: psql -v var=value (instead of -v x=y, you can use –set=x=y or –variable=x=y) you can set them using \set metacommand you can also set them to values from a query, using \gset, optionally with prefix To use them, you generally use :var query or metacommand. PostgreSQL is a powerful relational database management system that provides various features to enhance the functionality and flexibility of your applications. Running postmaster using the option -o -e to set dates to the European convention. Jun 4, 2025 · The psql command-line interface for PostgreSQL lets you pass parameters into your SQL scripts using variables. Dec 1, 2015 · How can I use query result stored into a record type variable for another query within the same stored function? I use Postgres 9. activeUserId}}; For example: This can be very useful for things like row security policies where we can use a session variable to only show rows that belong to the active user. Oct 9, 2025 · The SET command in PostgreSQL is used to configure session-level parameters. They can be used with SQL in place of any scalar value. &nbsp;Returning Data from Modified Rows # Sometimes it is useful to obtain data from modified rows while they are being … Aug 25, 2015 · While PostgreSQL’s procedural language PL/pgSQL supports approaches such as SELECT INTO and assignment (:=) to set PL/pgSQL variables based on a query result, these approaches are not supported for psql variable assignment. The variable itself is to be an integer, the loid of a large_object. The expressions can (and usually do) refer to columns computed in the FROM clause. As of postgresql 9. Write the query the same way as you would in an SQL SELECT command, but replace the initial keyword SELECT with PERFORM. Now I expected that a select statement using the variable with current_settings within the same transaction would be a Sep 19, 2019 · I am fairly new to Postgres and I cannot believe how difficult I am finding just to declare a variable. Must contain a dot - as opposed to Postgres settings (GUCs). But the variable is being interpreted as the table name instead of the value of the variable being interpreted as variable name. Also, the special variable FOUND is set to true if the query produced at least one row or false if it produced no rows. p_fb_config. I write a very simple query. They are typed. The psql --help command explains how to accomplish this: Apr 20, 2009 · Being completely new to PostgreSQL this threw me for a while, here's some more tips: + Make sure you end your statements with a semicolon! + Because there is no variable identifier you may want to use an _ or something similar to avoid ambiguous column names. This is a powerful technique for manipulating data in PostgreSQL. 4. I'm trying to run a simple query in plpgsql using a variable as table name in plpgsql. In addition, there are two commands that allow setting of defaults on a per-database or per-role basis: Jan 20, 2017 · For readability, use $$ instead of single quotes, set the psql variable with gset, then interpolate it as a string with :'<varname>' (note the quotes). 999 SELECT :aintconst AS aintconst, :arealconst AS realconst; aintconst | realconst -----------+----------- -333 | -9. (select <col_name> from OldTable where OldTable. For example: SET my. U Dec 23, 2022 · SET MY_CONSTANT TO 123; -- declared SET is an SQL command. psql supports advanced scripting, and psql scripts can be viewed as a superset of Postgres SQL dialect. They end with the session/process. Declaring a Record Type Variable in PostgreSQL Let us get a better understanding of the Record type variable in PostgreSQL from this article. Variables keep the mutable data that can be modified using a function or block code. xyz = 1; ALTER SYSTEM SET abc. In my table there are a few filed. Instead, the result of the select is consumed by an insert statement. Nov 13, 2025 · 6. Postgres support the SELECT statement to retrieve records from the zero or more tables or views in the database. In this post we’ll look at how you can use the build-in functions to set and get […] Dec 27, 2014 · In Postgres, I'm writing a test script for a function (stored procedure) I wrote. The stuff I've seen online all points to something like this: Jul 15, 2025 · In PostgreSQL, the select into statement to select data from the database and assign it to a variable. The manual: Custom options have two-part names: an extension name, then a dot, then the parameter name proper, much like qualified names in SQL. The PL/pgSQL SELECT INTO statement fetches the data from a particular table and assigns it to the given variable. 999 (1 row) Essentially what you want is the ability to script SQL. declare @foo varchar(50) = 'bar'; select @foo; How do you express this for postgres? Dec 31, 2024 · Learn how to declare and use variables in PostgreSQL with examples. The psql --help command explains how to accomplish this: How to assign the result of a query to a variable in PL/pgSQL? I have a function: Nov 13, 2025 · If SET LOCAL is used within a function that has a SET option for the same variable (see CREATE FUNCTION), the effects of the SET LOCAL command disappear at function exit; that is, the value in effect when the function was called is restored anyway. i just want to know if it is possible to declare variables on the DBeaver´s sql editor and use them on a query Feb 25, 2015 · I have written a Postgres anonymous block. Jan 20, 2015 · I currently use Firebird SQL as the db backend of my shareware, would like to support also PG 9. user_id in test; Why does the first one work but second? If I want to use a variable in where clause like the above, how can I do that? May 31, 2017 · I have this . I'm transforming rows from staging tables into other tables and adding value like the import date and the identity owning the inserts. PL/pgSQL variables are substituted in the query as usual. Setting the PGDATESTYLE environment variable. One of the essential skills for working with PostgreSQL is declaring variables in queries. Jun 25, 2020 · How in Postgresql inside a transaction to get values into a variable, and if SELECT did not return anything, throw an error, and if SELECT returned data, then use them in the transaction? Like th Jul 23, 2025 · In PostgreSQL, row type variables are handy when you need to store a whole row of data returned by a query. Apart from such compatibility considerations, it is best to use CREATE TABLE AS for this purpose in new code. Apr 10, 2022 · A session variable can be created by the command. In this tutorial, we'll focus exclusively on the SELECT statement itself, setting the foundation for more advanced queries in future lessons. + You can set the variable to a value in line using like this DECLARE _accountid INT := 1; Nov 13, 2025 · A variable's default value is evaluated and assigned to the variable each time the block is entered (not just once per function call). One of these filed is UserName . I'm trying to implement a query with start_time and end_time arguments, which the user can input their own dates into for customized results. Using PGAdmin III I can right-click on a database, navigate to the Variables tab, and put a variable name-value property on the database itself. For example, it supports commands Nov 13, 2025 · PostgreSQL allows columns of a table to be defined as variable-length multidimensional arrays. . This statement allows you to retrieve specific column values from a query result and store them in variables. 1, in psql you can now use :'variable' to have it properly quoted as a value for you, or :"variable" to use it as an identifier. Just remember, when you need to quote the value in SQL statement, use apostrophes around variable name, like this: SELECT * FROM foo WHERE bar = :'v3'; May 4, 2021 · PostgreSQL comes with a rich set of administrative functions for various use cases. It's these values that are provided by the variables - they are used in several such transforms and the point of the variable Nov 13, 2025 · The PostgreSQL usage of SELECT INTO to represent table creation is historical. What is a variable in PostgreSQL? In PostgreSQL, a variable allows a programmer to store data temporarily during the execution of code. Some other SQL implementations also use SELECT INTO in this way (but most SQL implementations support CREATE TABLE AS instead). You'll also understand variable scopes in PL/pgSQL. declare @foo varchar(50) = 'bar'; select @foo; How do you express this for postgres? Mar 19, 2024 · In this tutorial, you will learn how to declare PL/pgSQL variables in blocks and how to use variables effectively. 3 query? In MS SQL Server I can do this: DECLARE @myvar INT; SET @myvar = 5/ SELECT * FROM somewhere WHERE something = @myvar; How do I d Jan 15, 2021 · This is useful for things like injecting constant values where a select is providing the input to an insert table when copying from a staging table. p_gplus_config from a. An example is plpgsql. SELECT auc_user_insert(:'username', :'emailadr', :'password') AS oid; \gset SELECT auc_user_select(:oid); SELECT auc_user_delete(:oid); \gset is a new meta-command since psql 9. In FB I use set/get_context to do this: set-context get-context e. PostgreSQL Set Variable From Select? In this informative video, we’ll guide you through the process of storing query results in variables using PostgreSQL. May 27, 2025 · The SET command in PostgreSQL is primarily used to assign values to server-level configuration parameters. PL/pgSQL variables will be substituted into the query as usual. In the test script I want to select that id into a va Jan 24, 2024 · Summary: in this tutorial, you will learn how to use the PostgreSQL SELECT INTO statement to create a new table from the result set of a query. + + + + The value of a session variable is set with the SQL + command. I have a table called PgFinalLocationsTable on public schema. fglmr dac iahbr ibji ndro xgo wiuwp xgitc kwhqd ftufww tcylmt ywvm fckatm vwl vvl