小编Art*_*ski的帖子

我想从 plpgsql 函数返回表。

这是我的代码。

    CREATE FUNCTION test() RETURNS my_table AS
    $BODY$DECLARE
        q4 my_table;
    BEGIN
        q4 := SELECT * FROM my_table;
        RETURN q4;
    END;$BODY$
    LANGUAGE sql;

我收到以下错误：

    Error: ERROR:  syntax error at or near "SELECT"
    LINE 5:  q4 := SELECT * FROM my_table;

我从这个问题/教程开始。 https://dba.stackexchange.com/questions/35721/declare-variable-of-table-type-in​​-pl-pgsql && http://postgres.cz/wiki/PL/pgSQL_%28en%29

这个想法是我需要将此查询分配给一个变量。这只是我想创建的功能的一小部分。

第二个问题是如何遍历该集合并进行一些数学运算并为该表的某个字段赋值。但是首先我想解决这个问题。

我有一个 CMake 项目，具有以下结构：

cmake_minimum_required(VERSION 3.11)
project(ReadGraph)

# Download and unpack googletest at configure time
configure_file(CMakeLists.txt.in googletest-download/CMakeLists.txt)
execute_process(COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}" .
  RESULT_VARIABLE result
  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/googletest-download )
if(result)
  message(FATAL_ERROR "CMake step for googletest failed: ${result}")
endif()
execute_process(COMMAND ${CMAKE_COMMAND} --build .
  RESULT_VARIABLE result
  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/googletest-download )
if(result)
  message(FATAL_ERROR "Build step for googletest failed: ${result}")
endif()

# Add googletest directly to our build. This defines
# the gtest and gtest_main targets.
add_subdirectory(${CMAKE_CURRENT_BINARY_DIR}/googletest-src
                 ${CMAKE_CURRENT_BINARY_DIR}/googletest-build
                 EXCLUDE_FROM_ALL)

SET(CMAKE_CXX_FLAGS "-std=c++20 -pthread -O3")
include_directories(include)

enable_testing()
file(GLOB TESTS "test/*.cpp" …