问CMake错误: MYSQL_INCLUDE_DIR未找到

EN

cmake_minimum_required(VERSION 3.2)
include(CheckCXXSymbolExists)
project (sqlpp11-connector-mysql)
enable_testing()
set(CMAKE_CXX_STANDARD 11)

check_cxx_symbol_exists(_LIBCPP_VERSION iostream HAS_LIBCPP_VERSION)
if (HAS_LIBCPP_VERSION)
    message("libc++ does not have thread_local, thus we need to wrap that via boost thread")
    find_package(Boost COMPONENTS thread)
endif()


set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
find_package(MySql REQUIRED)

message(STATUS "Using ${CMAKE_CXX_COMPILER} (compiler id: ${CMAKE_CXX_COMPILER_ID})")

set(DATE_INCLUDE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../date" CACHE FILEPATH "Path to Howard Hinnant's date library")

if(NOT EXISTS ${DATE_INCLUDE_DIR}/date.h)
    message(SEND_ERROR "Can't find file date.h")
    message("Can't find date.h in ${DATE_INCLUDE_DIR} ")
    message("Please either")
    message("  - git clone https://github.com/howardhinnant/date ${DATE_INCLUDE_DIR}")
    message("  - download and unzip a current version from https://github.com/howardhinnant/date to ${DATE_INCLUDE_DIR}")
    message("  - set DATE_INCLUDE_DIR to point to the dir containing date.h from the date library")
    message("")
else()
    message("including date from ${DATE_INCLUDE_DIR}")
endif()

set(SQLPP11_INCLUDE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../sqlpp11/include" CACHE FILEPATH "Path to sqlpp11 includes")

if(NOT EXISTS ${SQLPP11_INCLUDE_DIR}/sqlpp11/sqlpp11.h)
    message(SEND_ERROR "Can't find file sqlpp11/sqlpp11.h")
    message("Can't find sqlpp11/sqlpp11.h in ${SQLPP11_INCLUDE_DIR} ")
    message("Please either")
    message("  - git clone https://github.com/rbock/sqlpp11 ${SQLPP11_INCLUDE_DIR}")
    message("  - download and unzip a current version from https://github.com/rbock/sqlpp11 to ${SQLPP11_INCLUDE_DIR}")
    message("  - set DATE_INCLUDE_DIR to point to the dir containing sqlpp11/sqlpp11.h")
    message("")
else()
    message("including sqlpp11 from ${SQLPP11_INCLUDE_DIR}")
endif()

set(MYSQL_INCLUDE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../include/sqlpp11/mysql" CACHE FILEPATH "PATH TO sqllpp11/mysql")

include_directories("${SQLPP11_INCLUDE_DIR}")
include_directories("${DATE_INCLUDE_DIR}")
include_directories("${MYSQL_INCLUDE_DIRS}")
set(include_dir "${PROJECT_SOURCE_DIR}/include")
file(GLOB_RECURSE sqlpp_headers ${include_dir}/*.h ${SQLPP11_INCLUDE_DIR}/*.h)
include_directories(${include_dir})

add_subdirectory(src)
add_subdirectory(tests)

install(DIRECTORY "${PROJECT_SOURCE_DIR}/include/sqlpp11" DESTINATION include)