The Ring programming language version 1.10 book - Part 37 of 212
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This document provides documentation on MySQL functions in the Ring programming language. It describes functions for connecting to a MySQL database, executing queries, retrieving results, and managing transactions. Example code is provided to demonstrate connecting to a database, creating tables, inserting and retrieving data, handling errors, and using transactions with commit and rollback.
![Ring Documentation, Release 1.10
41.17 Restore Image From The Database
Example:
con = mysql_init()
See "Connect to database..." + nl
mysql_connect(con, "localhost", "root", "root","mahdb")
See "Read data from database..." + nl
mysql_query(con,"SELECT data FROM photo WHERE id=1")
See "Write new file" + nl
result = mysql_result(con)
write("testsmahmoud2.jpg",result[1][1])
See "Close database..." + nl
mysql_close(con)
Output:
Connect to database...
Read data from database...
Write new file
Close database...
41.18 MySQL_AutoCommit() Function
We can enable or disable the auto commit feature using the MySQL_AutoCommit() function.
Syntax:
MySQL_AutoCommit(MySQL Handle, lStatus) # lstatus can be True/False
41.19 MySQL_Commit() Function
We can commit updates to the database using the MySQL_Commit() function.
Syntax:
MySQL_Commit(MySQL Handle)
41.20 MySQL_Rollback() Function
We can rollback updates to the database using the MySQL_Rollback() function.
Syntax:
MySQL_Rollback(MySQL Handle)
41.21 Transaction Example
The next example presents the usage of MySQL_Autocommit(), MySQL_Commit() & MySQL_RollBack() functions.
Example:
41.17. Restore Image From The Database 336](https://image.slidesharecdn.com/361ring-190427182052/85/The-Ring-programming-language-version-1-10-book-Part-37-of-212-9-320.jpg)
The Ring programming language version 1.10 book - Part 37 of 212
- 1. Ring Documentation, Release 1.10 See "Write image file" + nl write("testsgreat.jpg",hex2str( odbc_getdata(pODBC,3) ) ) ok See "Close database..." + nl odbc_disconnect(pODBC) odbc_close(pODBC) 40.21. Save and Restore images 328
- 2. CHAPTER FORTYONE MYSQL FUNCTIONS In this chapter we are going to learn about the MySQL functions provided by the Ring programming language. • MySQL_Info() • MySQL_Init() • MySQL_Error() • MySQL_Connect() • MySQL_Close() • MySQL_Query() • MySQL_Insert_ID() • MySQL_Result() • MySQL_Next_Result() • MySQL_Columns() • MySQL_Result2() • MySQL_Escape_String() • MySQL_AutoCommit() • MySQL_Commit() • MySQL_Rollback() Before using the next function load the mysqllib.ring library load "mysqllib.ring" # Use MySQL functions 41.1 MySQL_Info() Function We can get the MySQL Client version using the MySQL_Info() function. Syntax: MySQL_Info() ---> string contains the MySQL Client version Example: see "MySQL Client Version : " + mysql_info() 329
- 3. Ring Documentation, Release 1.10 Output: MySQL Client Version : 6.1.5 41.2 MySQL_Init() Function We can start using MySQL Client through the MySQL_Init() function. Syntax: MySQL_Init() ---> MySQL Handle 41.3 MySQL_Error() Function We can get the error message from the MySQL Client using the MySQL_Error() function. Syntax: MySQL_Error(MySQL Handle) ---> Error message as string 41.4 MySQL_Connect() Function We can connect to the MySQL database server using the MySQL_Connect() function. Syntax: MySQL_Connect(MySQL Handle, cServer, cUserName, cPassword) ---> lStatus 41.5 MySQL_Close() Function We can close the connection to the MySQL database using the MySQL_Close() function Syntax: MySQL_Close(MySQL Handle) 41.6 MySQL_Query() Function We can execute SQL queries using the MySQL_Query() function Syntax: MySQL_Query(MySQL Handle, cSQLQuery) 41.2. MySQL_Init() Function 330
- 4. Ring Documentation, Release 1.10 41.7 Create Database The next example connect to MySQL Server then create new database. See "MySQL Test - Create Database" + nl con = mysql_init() See "Connect" + nl if mysql_connect(con,"localhost","root","root") = 0 see "Cann't connect" + nl see "Error : " + mysql_error(con) + nl mysql_close(con) bye ok See "Create Database..." + nl mysql_query(con,"CREATE DATABASE mahdb") See "Close Connection" + nl mysql_close(con) Output: MySQL Test - Create Database Connect Create Database... Close Connection 41.8 Create Table and Insert Data The next example create new table and insert records func main see "Create Table and Insert Records" + nl con = mysql_init() see "Connect" + nl if mysql_connect(con, "localhost", "root", "root","mahdb") = 0 system_error(con) ok see "Drop table" + nl if mysql_query(con, "DROP TABLE IF EXISTS Employee") system_error(con) ok see "Create table" + nl if mysql_query(con, "CREATE TABLE Employee(Id INT, Name TEXT, Salary INT)") system_error(con) ok see "Insert data" + nl if mysql_query(con, "INSERT INTO Employee VALUES(1,'Mahmoud',15000)") system_error(con) ok if mysql_query(con, "INSERT INTO Employee VALUES(2,'Samir',16000)") system_error(con) ok if mysql_query(con, "INSERT INTO Employee VALUES(3,'Fayed',17000)") 41.7. Create Database 331
- 5. Ring Documentation, Release 1.10 system_error(con) ok see "Close connection" + nl mysql_close(con) func system_error con see mysql_error(con) mysql_close(con) bye Output: Create Table and Insert Records Connect Drop table Create table Insert data Close connection 41.9 MySQL_Insert_ID() Function We can get the inserted row id using the MySQL_Insert_ID() function Syntax: MySQL_Insert_ID() ---> Inserted row id as number Example: con = mysql_init() see "connect to database" + nl mysql_connect(con,"localhost","root","root","mahdb") see "drop table" + nl mysql_query(con, "DROP TABLE IF EXISTS Customers") see "create table" + nl mysql_query(con, "CREATE TABLE Customers(Id INT PRIMARY KEY AUTO_INCREMENT, Name TEXT)") see "insert record" + nl mysql_query(con, "INSERT INTO Customers(Name) VALUES('Mahmoud')") see "insert record" + nl mysql_query(con, "INSERT INTO Customers(Name) VALUES('Samir')") see "insert record" + nl mysql_query(con, "INSERT INTO Customers(Name) VALUES('Fayed')") see "insert record" + nl mysql_query(con, "INSERT INTO Customers(Name) VALUES('Test 2015')") see "inserted row id : " + mysql_insert_id(con) + nl see "close database" + nl mysql_close(con) Output: connect to database drop table create table insert record insert record insert record insert record inserted row id : 4 close database 41.9. MySQL_Insert_ID() Function 332
- 6. Ring Documentation, Release 1.10 41.10 MySQL_Result() Function We can get the query result (data without column names) using the MySQL_Result() function. Syntax: MySQL_Result(MySQL Handle) ---> List contains the query result 41.11 MySQL_Next_Result() Function We can move to the next query result using the MySQL_Next_Result() function. We use this function when we have multiple SQL statements in the same query. Syntax: MySQL_Next_Result(MySQL Handle) 41.12 Print Query Result The next example execute a query on the database then print the result. con = mysql_init() see "Connect to database" + nl mysql_connect(con, "localhost", "root", "root","mahdb") see "Execute Query" + nl mysql_query(con, "SELECT Name FROM Employee WHERE Id=1;"+ "SELECT Name FROM Employee WHERE Id=3") see "Print Result" + nl see mysql_result(con) mysql_next_result(con) see mysql_result(con) see "close database" + nl mysql_close(con) Output: Connect to database Execute Query Print Result Mahmoud Fayed close database 41.13 MySQL_Columns() Function We can get a list of columns names using the MySQL_Columns() function. Syntax: 41.10. MySQL_Result() Function 333
- 7. Ring Documentation, Release 1.10 MySQL_Columns(MySQL Handle) ---> List contains columns information Example: con = mysql_init() see "Connect to database" + nl mysql_connect(con, "localhost", "root", "root","mahdb") see "Execute Query" + nl mysql_query(con, "SELECT * FROM Employee") see "Result" + nl see mysql_columns(con) see "Close database" + nl mysql_close(con) Output: Connect to database Execute Query Result Id 11 3 32768 Name 65535 252 16 Salary 11 3 32768 Close database 41.14 MySQL_Result2() Function Instead of using MySQL_Result() to get the result data without columns names, we can use the MySQL_Result2() to get all of the column names then the query result in one list. Syntax: MySQL_Result2(MySQL Handle) ---> List (query result starts with columns names) Example: con = mysql_init() see "Connect to database" + nl mysql_connect(con, "localhost", "root", "root","mahdb") see "Execute Query" + nl mysql_query(con, "SELECT * FROM Employee") see "Print Result" + nl see mysql_result2(con) see "Close database" + nl mysql_close(con) Output: 41.14. MySQL_Result2() Function 334
- 8. Ring Documentation, Release 1.10 Connect to database Execute Query Print Result Id Name Salary 1 Mahmoud 15000 2 Samir 16000 3 Fayed 17000 Close database 41.15 MySQL_Escape_String() Function We can store binary data and special characters in the database after processing using MySQL_Escape_String() func- tion Syntax: MySQL_Escape_String(MySQL Handle, cString) ---> String after processing 41.16 Save Image inside the database Example: See "Read file" + nl cFile = read("testsmahmoud.jpg") con = mysql_init() See "Connect to database..." + nl mysql_connect(con, "localhost", "root", "root","mahdb") See "Escape string..." + nl cFile = mysql_escape_string(con,cFile) stmt = "INSERT INTO photo(id, data) VALUES(1, '" + cFile + "')" See "Insert data..." + nl mysql_query(con,stmt) See "Close database..." + nl mysql_close(con) Output: Read file Connect to database... Escape string... Insert data... Close database... 41.15. MySQL_Escape_String() Function 335
- 9. Ring Documentation, Release 1.10 41.17 Restore Image From The Database Example: con = mysql_init() See "Connect to database..." + nl mysql_connect(con, "localhost", "root", "root","mahdb") See "Read data from database..." + nl mysql_query(con,"SELECT data FROM photo WHERE id=1") See "Write new file" + nl result = mysql_result(con) write("testsmahmoud2.jpg",result[1][1]) See "Close database..." + nl mysql_close(con) Output: Connect to database... Read data from database... Write new file Close database... 41.18 MySQL_AutoCommit() Function We can enable or disable the auto commit feature using the MySQL_AutoCommit() function. Syntax: MySQL_AutoCommit(MySQL Handle, lStatus) # lstatus can be True/False 41.19 MySQL_Commit() Function We can commit updates to the database using the MySQL_Commit() function. Syntax: MySQL_Commit(MySQL Handle) 41.20 MySQL_Rollback() Function We can rollback updates to the database using the MySQL_Rollback() function. Syntax: MySQL_Rollback(MySQL Handle) 41.21 Transaction Example The next example presents the usage of MySQL_Autocommit(), MySQL_Commit() & MySQL_RollBack() functions. Example: 41.17. Restore Image From The Database 336
- 10. Ring Documentation, Release 1.10 func main con = mysql_init() see "Connect" + nl if mysql_connect(con, "localhost", "root", "root","mahdb") = 0 system_error(con) ok see "Drop table" + nl if mysql_query(con, "DROP TABLE IF EXISTS Employee2") system_error(con) ok see "Create table" + nl if mysql_query(con, "CREATE TABLE Employee2(Id INT, Name TEXT, Salary INT)") system_error(con) ok see "Insert data" + nl if mysql_query(con, "INSERT INTO Employee2 VALUES(1,'Mahmoud',15000)") system_error(con) ok if mysql_query(con, "INSERT INTO Employee2 VALUES(2,'Samir',16000)") system_error(con) ok if mysql_query(con, "INSERT INTO Employee2 VALUES(3,'Fayed',17000)") system_error(con) ok mysql_autocommit(con,False) mysql_query(con, "INSERT INTO Employee2 VALUES(4,'Ahmed',5000)") mysql_query(con, "INSERT INTO Employee2 VALUES(5,'Ibrahim',50000)") mysql_query(con, "INSERT INTO Employee2 VALUES(6,'Mohammed',50000)") See "Save transaction (y/n) " give nChoice if upper(nChoice) = "Y" mysql_commit(con) else mysql_rollback(con) ok see "Close connection" + nl mysql_close(con) func system_error con see mysql_error(con) mysql_close(con) bye Output: Connect Drop table Create table Insert data Save transaction (y/n) y Close connection 41.21. Transaction Example 337