ucasfl

#include <iostream>
#include <vector>

namespace A
{
class Array
{
public:
    Array() = default;
    void test() { }

ucasfl

# This is the CMakeCache file.
# For build in directory: /essd/fenglv/ClickHouse/rel
# It was generated by CMake: /essd/fenglv/gentoo/usr/bin/cmake
# You can edit this file to change values found and used by cmake.
# If you do not want to change any of the values, simply exit the editor.
# If you do want to change a value, simply edit, save, and exit the editor.
# The syntax for the file is as follows:
# KEY:TYPE=VALUE
# KEY is the name of a variable in the cache.
# TYPE is a hint to GUIs for the type of VALUE, DO NOT EDIT TYPE!.

ucasfl

#include <iostream>
#include <vector>
using namespace std;

int maxDiff(std::vector<int> & nums)
{
    if (nums.size() <= 1)
        return 0;
    vector<int> max_v;

ucasfl

#include <getopt.h>                                                                                                                                               
#include <stdio.h>                                                                                                                                                
#include <stdlib.h>                                                                                                                                               
#include <unistd.h>                                                                                                                                               
                                                                                                                                                                  
extern int optind, opterr, optopt;                                                                                                                                
extern char * optarg;                         

ucasfl

DROP DATABASE IF EXISTS yg_projection;

CREATE DATABASE yg_projection;

USE yg_projection;

CREATE TABLE app_flow_entrance_data_detail_local
(
   `hour` Int32,
   `minute` Int32,

ucasfl

#include <iostream>
#include <thread>
#include <vector>

class A
{
public:
    void func()
    {
        auto f = [&](int i) { vec[i] = i; };

ucasfl

如何在ClickHouse中添加自定义函数

在数据库中，通常有三类不同的函数，简称UDF，UDAF和UDTF。

UDF是指用户自定义函数，在ClickHouse中，这类函数不会改变数据的行数，其会对输入的列进行相应的计算，产生新的数据列。

UDAF是指用户自定义聚合函数，数据库中常见的sum、count等函数即为聚合函数，这类函数对输入的数据进行聚合计算，最终只输出一个聚合后的数据。

UDTF是指用户自定义表函数，正如名字所示，这类函数会返回一个临时的表（Table），从而可以通过SELECT语句从中读取数据，甚至通过INSERT语句插入数据。

ucasfl

struct CustomizeASTSelectWithUnionQueryNormalize
{
    using TypeToVisit = ASTSelectWithUnionQuery;

    const UnionMode & union_default_mode;

    static void getSelectsFromUnionListNode(ASTPtr & ast_select, ASTs & selects)
    {
        if (auto * inner_union = ast_select->as<ASTSelectWithUnionQuery>())
        {

ucasfl

#include <Parsers/ASTExpressionList.h>
#include <Parsers/ASTSelectWithUnionQuery.h>
#include <Parsers/ExpressionListParsers.h>
#include <Parsers/ParserSelectWithUnionQuery.h>
#include <Parsers/ParserUnionQueryElement.h>
#include <Common/typeid_cast.h>

namespace DB
{
static void getSelectsFromUnionListNode(ASTPtr & ast_select, ASTs & selects)

ucasfl

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dlfcn.h>

int main(int argc, char** argv)
{
    void *handle;
    void (*func_print_name)(const char*);