[AntDB database] AntDB database service start and stop (2)

Database service start and stop

Connect to AntDB

If you have experience using python to connect to postgres, the operation in AntDB is exactly the same. First you need to import psycopg2, and then use the conn method provided by psycopg2 to create a connection. The code example is as follows:

import psycopg2
conn = psycopg2.connect(database="postgres", user="dang31", password="123", host="10.1.226.256", port="1234")

At this point, a connection is created for subsequent use. Before performing database operations, you need to create a cursor first, and perform corresponding operations in the cursor:

cur = conn.cursor()

Create table:

cur.execute("create t_test (id int,name text)")

Insert data:

cur.insert("insert into t_test values (1,'name')")

delete data:

cur.execute("delete from t_test where id=%s",(3,)) 

update data:

cur.execute("update  t_test set name=%s where id=%s",('c',1)) 

Query data:

cur.execute("select * from t_test;")
rows = cur.fetchall()
pprint.pprint(rows)

The complete script is as follows:

#!/usr/bin/env python
# -*- coding: UTF-8 -*-

import psycopg2
import sys
import pprint

adb_conn="dbname=postgres user=dang31 password=123 host=10.1.226.256 port=1234"

try:
   conn = psycopg2.connect(adb_conn)
except psycopg2.Error as e:
    print"Unable to connect!"
    print e.pgerror
    print e.diag.message_detail
    sys.exit(1)
else:
    print"Connected!"    
    cur = conn.cursor()
#该程序创建一个光标将用于整个数据库使用Python编程。
print ("version:")
cur.execute("select version();")  
rows = cur.fetchall()
pprint.pprint(rows)
print ("create  table")
cur.execute("create table t_test (id int,name text);")   
print ("insert into table")
cur.execute("insert into t_test (id,name) values (%s,%s)",(1,'a'))
cur.statusmessage
cur.execute("insert into t_test (id,name) values (%s,%s)",(3,'b')) 
cur.mogrify("insert into t_test (id,name) values (%s,%s)",(3,'b')) 
cur.execute("select * from t_test;")
print ("fetchone")
row = cur.fetchone()
pprint.pprint(row)
cur.execute("select * from t_test;")
rows = cur.fetchall()
print ("fetchall")
pprint.pprint(rows)
print ("delete from table")
cur.execute("delete from t_test where id=%s",(3,)) 
cur.execute("select * from t_test;")
rows = cur.fetchall()
pprint.pprint(rows)
print ("update  table")
cur.execute("update  t_test set name=%s where id=%s",('c',1)) 
cur.execute("select * from t_test;")
rows = cur.fetchall()
pprint.pprint(rows)
print ("drop  table")
cur.execute("drop table if EXISTS  t_test ");

conn.commit()
#connection.commit() 此方法提交当前事务。如果不调用这个方法，无论做了什么修改，自从上次调用#commit()是不可见的，从其他的数据库连接。
conn.close() 
#connection.close() 此方法关闭数据库连接。请注意，这并不自动调用commit（）。如果你只是关闭数据库连接而不调用commit（）方法首先，那么所有更改将会丢失

The output is:

Connected!
version:
[('PostgreSQL 11.6 ADB 5.0.0 37c61ca18f on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-36), 64-bit',)]
create  table
insert into table
fetchone
(3, 'b')
fetchall
[(1, 'a'), (3, 'b')]
delete from table
[(1, 'a')]
update  table
[(1, 'c')]
drop  table

For more operations, please refer to the documentation of psycopg: https://www.psycopg.org/docs/index.html

C++ connection

In C++, different databases can be accessed through the OTL template library. We recommend using OTL+ODBC to access AntDB.

OTL documentation: http://otl.sourceforge.net/otl3.htm

Configure OBDC

1. Install the ODBC development package:

yum install unixODBC-devel

1. 安装pg odbc： psqlodbc - PostgreSQL ODBC driver PostgreSQL: File Browser

wget  https://ftp.postgresql.org/pub/odbc/versions/src/psqlodbc-11.01.0000.tar.gz
tar xzvf psqlodbc-11.01.0000.tar.gz 
cd psqlodbc-11.01.0000 
./configure 
make 
make install #root 执⾏

The installation path is as follows:

/bin/mkdir -p '/usr/local/lib' 
/bin/sh ./libtool --mode=install /bin/install -c psqlodbcw.la psqlodbca.la '/usr/local/lib' 
libtool: install: /bin/install -c .libs/psqlodbcw.so /usr/local/lib/psqlodbcw.so 
libtool: install: /bin/install -c .libs/psqlodbcw.lai /usr/local/lib/psqlodbcw.la 
libtool: install: /bin/install -c .libs/psqlodbca.so /usr/local/lib/psqlodbca.so 
libtool: install: /bin/install -c .libs/psqlodbca.lai /usr/local/lib/psqlodbca.la 
libtool: finish: PATH="/data/sy/hive/hive-2.3.3/bin:/data/sy/hadoop/hadoop-2.8.5/bin:/data/sy/hadoop/hadoop-
2.8.5/sbin:/data/sy/jdk/jdk1.8.0_191/bin:/data/sy/jdk/jdk1.8.0_191/jre/bin:/home/adb40sy/mysql/install/bin:/data/sy/hive/h ive-2.3.3/bin:/data/sy/hadoop/hadoop-2.8.5/bin:/data/sy/hadoop/hadoop-
2.8.5/sbin:/data/sy/jdk/jdk1.8.0_191/bin:/data/sy/jdk/jdk1.8.0_191/jre/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/ sbin:/usr/bin:/root/bin:/usr/local/madlib/Versions/1.15/bin:/sbin" ldconfig -n /usr/local/lib

---------------------------------------------------------------------Libraries have been installed in:
/usr/local/lib
If you ever happen to want to link against installed libraries in a given directory, LIBDIR, you must either use libtool, and specify the full pathname of the library, or use the `-LLIBDIR' flag during linking and do at least one of the following:
- add LIBDIR to the `LD_LIBRARY_PATH' environment variable during execution
- add LIBDIR to the `LD_RUN_PATH' environment variable during linking
- use the `-Wl,-rpath -Wl,LIBDIR' linker flag
- have your system administrator add LIBDIR to `/etc/ld.so.conf'
See any operating system documentation about shared libraries for more information, such as the ld(1) and ld.so(8) manual pages.

1. isql test:

**********************************************
* unixODBC - isql                            *
**********************************************
* Syntax                                     *
*                                            *
*      isql DSN [UID [PWD]] [options]        *
*                                            *
* Options                                    *
*                                            *
* -b         batch.(no prompting etc)        *
* -dx        delimit columns with x          *
* -x0xXX     delimit columns with XX, where  *
*            x is in hex, ie 0x09 is tab     *
* -w         wrap results in an HTML table   *
* -c         column names on first row.      *
*            (only used when -d)             *
* -mn        limit column display width to n *
* -v         verbose.                        *
* -lx        set locale to x                 *
* -q         wrap char fields in dquotes     *
* -3         Use ODBC 3 calls                *
* -n         Use new line processing         *
* -e         Use SQLExecDirect not Prepare   *
* -k         Use SQLDriverConnect            *
* --version  version                         *
*                                            *
* Commands                                   *
*                                            *
* help - list tables                         *
* help table - list columns in table         *
* help help - list all help options          *
*                                            *
* Examples                                   *
*                                            *
*      isql WebDB MyID MyPWD -w < My.sql     *
*                                            *
*      Each line in My.sql must contain      *
*      exactly 1 SQL command except for the  *
*      last line which must be blank (unless *
*      -n option specified).                 *
*                                            *
* Please visit;                              *
*                                            *
*      http://www.unixodbc.org               *
*      [email protected]                      *
*      [email protected]              *
**********************************************

1. Modify the odbc default configuration (vi /etc/odbcinst.ini):

Default PG configuration:

[PostgreSQL]
Description     = ODBC for PostgreSQL
Driver          = /usr/lib64/psqlodbc.so
#Driver         = /usr/lib/psqlodbcw.so
#Setup          = /usr/lib/libodbcpsqlS.so
#Driver64       = /usr/lib64/psqlodbcw.so
#Setup64        = /usr/lib64/libodbcpsqlS.so
FileUsage       = 1

You can leave this configuration parameter unchanged, find the above file in your own environment, and create a soft link:

root@intel175 ~]# find / -name 'psqlodbcw.so'
/ssd/home/billing/soft/psqlodbc-11.01.0000/.libs/psqlodbcw.so
/usr/local/lib/psqlodbcw.so
[root@intel175 ~]# find / -name 'libodbcpsqlS.so'
/usr/lib64/libodbcpsqlS.so

ln -s /usr/local/lib/psqlodbcw.so /usr/lib/otlobbc.so 
ln -s /usr/local/lib/psqlodbcw.so /usr/lib64/otlobbc.so
ln -s /usr/lib64/libodbcpsqlS.so /usr/lib/libodbcpsqlS.so

1. configure-dsn

vi /etc/odbc.ini

[antdb]
Description = Test to antdb 
Driver = PostgreSQL 
Database = postgres 
Servername = localhost 
UserName = billing
Password = billing 
Port = 4333

1. Connection test:

[billing@intel175 soft]$ isql antdb -v
+---------------------------------------+
| Connected!  |
| |
| sql-statement |
| help [tablename]  |
| quit  |
| |
+---------------------------------------+
SQL> select count(*) from pg_class;
+---------------------+
| count |
+---------------------+
| 380 |
+---------------------+
SQLRowCount returns 1
1 rows fetched SQL>

If the following error occurs when executing the isql test

[unixODBC][Driver Manager]Data source name not found, and no default driver specified

First confirm that the environment variable of odbc is correctly pointing to your own configuration file, and confirm the method

[antdb@adb01 mgr1]$dbcinst -j
unixODBC 2.3.1
DRIVERS............: /etc/odbcinst.ini  # 确认路径是上面配置odbcinst.ini文件路径
SYSTEM DATA SOURCES: /etc/odbc.ini      # 确认路径是上面配置odbc.ini文件路径
FILE DATA SOURCES..: /etc/ODBCDataSources
USER DATA SOURCES..: /home/antdb/.odbc.ini
SQLULEN Size.......: 8
SQLLEN Size........: 8
SQLSETPOSIROW Size.: 8

Then confirm the access permission of the /etc/odbc.ini file, and confirm that the user who executes isql has read permission

Operation database example through OTL

1. Create a file: test_antdb.cpp

#include <iostream>
using namespace std;

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

#define OTL_ODBC_UNIX // uncomment this line if UnixODBC is used
#define OTL_ODBC_ALTERNATE_RPC
#if !defined(_WIN32) && !defined(_WIN64)
#define OTL_ODBC
#else 
#define OTL_ODBC_POSTGRESQL // required with PG ODBC on Windows
#endif
#include "otlv4.h" // include the OTL 4.0 header file

otl_connect db; // connect object

void insert()
// insert rows into table
{ 
 otl_stream o(10000, // PostgreSQL 8.1 and higher, the buffer can be > 1
              "insert into test_tab values(:f1<int>,:f2<int>)", 
                 // SQL statement
              db // connect object
             );
 char tmp[8];
 for(int i=1;i<=10;++i){
  sprintf(tmp,"Name%d\0",i);
  // o<<i<<i*10;
  o<<i<<i;
  o.flush();
  cout<<"Number:"<<i<<endl;
 }
}
void update(const int af1)
// insert rows into table
{ 
 otl_stream o(1, // PostgreSQL 8.1 and higher, buffer size can be >1
              "UPDATE test_tab "
              "   SET f2=:f2<int> "
              " WHERE f1=:f1<int>", 
                 // UPDATE statement
              db // connect object
             );
 o<<otl_null()<<af1+1; // set f2 to NULL

}
void select(const int af1)
{ 
 otl_stream i(50, // On SELECT, the buffer size can be > 1
              "select * from test_tab where f1>=:f11<int> and f1<=:f12<int> and rownum < 10", 
                 // SELECT statement
              db // connect object
             ); 
   // create select stream

 int f1;
//  char f2[31];
 int f2;

#if (defined(_MSC_VER) && _MSC_VER>=1600) || defined(OTL_CPP_11_ON)
// C++11 (or higher) compiler
#if defined(OTL_ANSI_CPP_11_VARIADIC_TEMPLATES)
 otl_write_row(i,af1,af1); // Writing input values into the stream
#else
  // when variadic template functions are not supported by the C++
  // compiler, OTL provides nonvariadic versions of the same template
  // functions in the range of [1..15] parameters
 otl_write_row(i,af1,af1); // Writing input values into the stream
  // the old way (operators >>() / <<()) is available as always:
  // i<<af1<<af1; // Writing input values into the stream
#endif
 for(auto& it : i){
  it>>f1;
  cout<<"f1="<<f1<<", f2=";
  it>>f2;
  if(it.is_null())
   cout<<"NULL";
  else
   cout<<f2;
  cout<<endl;
 }
#else
// C++98/03 compiler
 i<<af1<<af1; // Writing input values into the stream
 while(!i.eof()){ // while not end-of-data
   i>>f1;
   cout<<"f1="<<f1<<", f2=";
   i>>f2;
   if(i.is_null())
     cout<<"NULL";
   else
     cout<<f2;
   cout<<endl;
 }
#endif

}

int main()
{
 otl_connect::otl_initialize(); // initialize ODBC environment
 try{

  //db.rlogon("scott/tiger@postgresql");
  //db.rlogon("billappxc/123@sunyu");
  db.rlogon("danghb/123@antdb");

  otl_cursor::direct_exec
   (
    db,
    "drop table IF EXISTS test_tab",
    otl_exception::disabled // disable OTL exceptions
   ); // drop table

  //  db.commit();

  otl_cursor::direct_exec
   (
    db,
    "create table test_tab(f1 bigint, f2 bigint)"
    );  // create table

  otl_cursor::direct_exec
   (
    db,
    "set grammar to oracle"
    );  // set grammar

  // db.commit();
  insert(); // insert records into the table
  //db.commit();
  //return 0;
  update(10); // update records in the table
  select(8); // select records from the table
  select(3); // select records from the table
  select(5); // select records from the table
  db.commit();
 }

 catch(otl_exception& p){ // intercept OTL exceptions
  cerr<<p.msg<<endl; // print out error message
  cerr<<p.stm_text<<endl; // print out SQL that caused the error
  cerr<<p.sqlstate<<endl; // print out SQLSTATE message
  cerr<<p.var_info<<endl; // print out the variable that caused the error
 }

 db.logoff(); // disconnect from ODBC

 return 0;
}

1. compile file

g++ test_antdb.cpp -L/usr/lib -lotlobbc -o test_antdb -g

1. execute program

./test_antdb
Number:1
Number:2
Number:3
Number:4
Number:5
Number:6
Number:7
Number:8
Number:9
Number:10
f1=8, f2=8
f1=3, f2=3
f1=5, f2=5

Note: When using bind variables in the program, it is necessary to ensure that the bind variable type is consistent with the passed value type, otherwise an error will be reported:

Incompatible data types in stream operation
UPDATE test_tab    SET f2=?         WHERE f1=?       

Variable: :f2<INT>, datatype in operator <</>>: CHAR

The AntDB database began in 2008. On the core system of the operator, it provides online services for more than 1 billion users in 24 provinces across the country. It has product features such as high performance, elastic expansion, and high reliability. It can process millions of transactions per second at peak Telecom core transactions have ensured the continuous and stable operation of the system for nearly ten years, and have been successfully commercialized in industries such as communications, finance, transportation, energy, and the Internet of Things.