The Ring programming language version 1.4.1 book - Part 7 of 31

Ring Documentation, Release 1.4.1
Ungetc(file handle,character)
29.26 Fread() Function
We can read data from a stream using the Fread() function
Syntax:
Fread(file handle,nSize)
29.27 Fwrite() Function
We can write data to a stream using the Fwrite() function
Syntax:
Fwrite(file handle,cString)
29.28 Fexists() Function
We can check if a ﬁle exists using the Fexists() function
Syntax:
Fexists(cFileName) ---> returns 1 if the file exists
Example:
see fexists("b:mahmoudappsringring.exe") + nl +
fexists("b:mahmoudappsringring2.exe") + nl
Output:
1
0
29.29 Example
The next program test some of the ﬁle functions
See "testing file functions" + nl
See "open file" + nl
fp = fopen(exefolder() + "../tests/scripts/s65.ring","r")
See "reopen" + nl
fp = freopen(exefolder() + "../tests/scripts/s78.ring","r",fp)
See "close file" + nl
fclose(fp)
see "temp file" + nl
29.26. Fread() Function 158

fp = tempfile()
fclose(fp)
see "temp name" + nl
see tempname() + nl
remove(exefolder() + "../tests/scripts/mytest2.txt")
write(exefolder() + "../tests/scripts/tests1.txt","hello")
rename(exefolder() + "../tests/scripts/test1.txt",exefolder() +
"../tests/scripts/mytests2.txt")
see "print file" + nl
fp = fopen(exefolder() + "../samples/fromdoc/filefuncs.ring","r")
r = fgetc(fp)
while isstring(r)
see r
r = fgetc(fp)
end
fclose(fp)
see nl+"print line from the file" + nl
fp = fopen(exefolder() + "../samples/fromdoc/filefuncs.ring","r")
r = fgets(fp,33)
see r + nl
fclose(fp)
fp = fopen(exefolder() + "../tests/scripts/test78.txt","w+")
fseek(fp,0,2) # goto end of file
fputc(fp,"t")
fputc(fp,"e")
fputc(fp,"s")
fputc(fp,"t")
fputs(fp,"tests2")
fclose(fp)
see "print file" + nl
see read(exefolder() + "../tests/scripts/test78.txt")
fp = fopen(exefolder() + "../tests/scripts/test78.txt","r")
see "testing ungetc() " + nl
for x = 1 to 3
r = fgetc(fp)
see r + nl
ungetc(fp,r)
next
fclose(fp)
see "testing fread() " + nl
fp = fopen(exefilename(),"rb")
r = fread(fp,100)
see r + nl
fclose(fp)
see "testing fwrite() " + nl
fp = fopen(exefolder() + "../tests/scripts/test1.txt","wb")
fwrite(fp,r)
fclose(fp)
The next example print part of the content of a binary ﬁle
29.29. Example 159

see "Testing: fread()" +" FileName: "+ exefilename() +nl +nl
fp = fopen(exefilename(),"rb")
r = fread(fp,800)
for n =1 to len(r)
if isprint(substr(r, n, 1))
see substr(r, n, 1)
else
see "."
ok
### 80 char per line
if n % 80 = 0
see nl
ok
next
fclose(fp)
29.30 Numbers and Bytes
The next functions to convert between Numbers and Bytes.
• Int2Bytes()
• Float2Bytes()
• Double2Bytes()
• Bytes2Int()
• Bytes2Float()
• Bytes2Double()
Example:
see "Test Int2Bytes() and Bytes2Int() - Value : 77" + nl
r = Int2Bytes(77)
see "Int Size : " + len(r) + nl
see r + nl
see Bytes2Int(r) + nl
see "Test Float2Bytes() and Bytes2Float() - Value 77.12" + nl
r = Float2Bytes(77.12)
see "Float Size : " + len(r) + nl
see r + nl
see Bytes2Float(r) + nl
see "Test Double2Bytes() and Bytes2Double() - Value 9999977.12345" + nl
r = Double2Bytes(9999977.12345)
see "Double Size : " + len(r) + nl
see r + nl
decimals(5)
see Bytes2Double(r) + nl
29.30. Numbers and Bytes 160

CHAPTER
THIRTY
SYSTEM FUNCTIONS
In this chapter we are going to learn about the system functions
• System()
• SysGet()
• IsMSDOS()
• IsWindows()
• IsWindows64()
• IsUnix()
• IsMacOSX()
• IsLinux()
• IsFreeBSD()
• IsAndroid()
• Windowsnl()
• Get Command Line Arguments
• Get Active Source File Name
• CurrentDir()
• ExeFileName()
• ChDir()
• ExeFolder()
• Version()
30.1 System() Function
We can execute system commands using the system() function
Syntax:
System(cCommand)
Example:
System("myapp.exe") # Run myapp.exe
System("ls") # print list of files
161

30.2 SysGet() Function
We can get environment variables using the Get() function
Syntax:
SysGet(cVariable)
Example:
see sysget("path") # print system path information
30.3 IsMSDOS() Function
We can check if the operating system is MSDOS or not using the IsMSDOS() function
Syntax:
IsMSDOS() ---> Returns 1 if the operating system is MS-DOS, Returns 0 if it's not
30.4 IsWindows() Function
We can check if the operating system is Windows or not using the IsWindows() function
Syntax:
IsWindows() ---> Returns 1 if the operating system is Windows, Returns 0 if it's not
30.5 IsWindows64() Function
We can check if the operating system is Windows 64bit or not using the IsWindows64() function
Syntax:
IsWindows64() ---> Returns 1 if the operating system is Windows64, Returns 0 if it's not
30.6 IsUnix() Function
We can check if the operating system is Unix or not using the IsUnix() function
Syntax:
IsUnix() ---> Returns 1 if the operating system is Unix, Returns 0 if it's not
30.7 IsMacOSX() Function
We can check if the operating system is Mac OS X or not using the IsMacOSX() function
Syntax:
30.2. SysGet() Function 162

IsMacOSX() ---> Returns 1 if the operating system is Mac OS X, Returns 0 if it's not
30.8 IsLinux() Function
We can check if the operating system is Linux or not using the IsLinux() function
Syntax:
IsLinux() ---> Returns 1 if the operating system is Linux, Returns 0 if it's not
30.9 IsFreeBSD() Function
We can check if the operating system is FreeBSD or not using the IsFreeBSD() function
Syntax:
IsFreeBSD() ---> Returns 1 if the operating system is FreeBSD, Returns 0 if it's not
30.10 IsAndroid() Function
We can check if the operating system is Android or not using the IsAndroid() function
Syntax:
IsAndroid() ---> Returns 1 if the operating system is Android, Returns 0 if it's not
30.11 Example
see "IsMSDOS() --> " + ismsdos() + nl
see "IsWindows() --> " + iswindows() + nl
see "IsWindows64() --> " + iswindows64() + nl
see "IsUnix() --> " + isunix() + nl
see "IsMacOSX() --> " + ismacosx() + nl
see "IsLinux() --> " + islinux() + nl
see "IsFreeBSD() --> " + isfreebsd() + nl
see "IsAndroid() --> " + isandroid() + nl
Output:
IsMSDOS() --> 0
IsWindows() --> 1
IsWindows64() --> 0
IsUnix() --> 0
IsMacOSX() --> 0
IsLinux() --> 0
IsFreeBSD() --> 0
IsAndroid() --> 0
30.8. IsLinux() Function 163

30.12 Windowsnl() Function
We can get the windows new line string using the Windowsnl() function.
Syntax:
WindowsNL() ---> Returns a string contains CR+LF = CHAR(13) + CHAR(10)
Example:
cStr = read("input.txt")
if iswindows()
cStr = substr(cStr,windowsnl(),nl)
ok
aList = str2list(cStr)
# to do - list items processing using "for in"
cStr = list2str(aList)
if iswindows()
cStr = substr(cStr,nl,windowsnl())
ok
write("ouput.txt",cStr)
30.13 Get Command Line Arguments
We can get the command line arguments passed to the ring script using the sysargv variable.
The sysargv variable is a list contains the command line parameters.
Example
see copy("=",30) + nl
see "Command Line Parameters" + nl
see "Size : " + len(sysargv) + nl
see sysargv
see copy("=",30) + nl
if len(sysargv) < 4 return ok
nStart = sysargv[3]
nEnd = sysargv[4]
for x = nStart to nEnd
see x + nl
next
Output
b:mahmoudappsring>ring testssyspara.ring 1 10
==============================
Command Line Parameters
Size : 4
ring
testssyspara.ring
1
10
==============================
30.12. Windowsnl() Function 164

1
2
3
4
5
6
7
8
9
10
30.14 Get Active Source File Name
We can get the active source file name (*.ring) using the filename() function
Syntax:
filename() ---> String contains the active source file name.
Example:
see "Active Source File Name : " + filename() + nl
Output:
Active Source File Name : testsfilename.ring
Example:
if sysargv[2] = filename()
see "I'm the main program file!" + nl
# we can run tests here!
else
see "I'm a sub file in a program" + nl
ok
30.15 PrevFileName() Function
Using the PrevFileName() function we can get the previous active source file name.
The previous file would be the file of the caller function, Or the file of the function that we called before calling
PrevFileName().
Syntax:
prevfilename() ---> String contains the previous source file name.
Example:
The next function in stdlib.ring uses the PrevFileName() to know if the file of the caller function is the main source
file of the program or not.
Func IsMainSourceFile
if PrevFileName() = sysargv[2]
return true
ok
return false
30.14. Get Active Source File Name 165

30.16 CurrentDir() Function
Return the path of the current directory
Syntax:
CurrenDir() ---> String contains the path of the currect directory
30.17 ExeFileName() Function
Return the Ring executable ﬁle name
Syntax:
exefilename() ---> String contains the Ring executable file name
30.18 ChDir() Function
Change the current directory
Syntax:
ChDir(cNewPath)
30.19 ExeFolder() Function
Return the Ring executable ﬁle path
Syntax:
exefolder() ---> String contains the Ring executable path
30.20 Version() Function
Return the Ring version
Syntax:
version() ---> String contains the Ring version
Output:
1.4.1
30.16. CurrentDir() Function 166

CHAPTER
THIRTYONE
EVAL() AND DEBUGGING
In this chapter we are going to learn about
• Error Handling using Try/Catch/Done
• Eval() function
• Raise() function
• Assert() function
31.1 Try/Catch/Done
Syntax:
Try
Statements...
Catch
Statements...
Done
The statements in the Try block will be executed, if any error happens then the statements in the catch block will be
executed.
Inside the catch block we can use the variable cCatchError to get the error message
Example:
Try
see 5/0
Catch
see "Catch!" + nl + cCatchError
Done
Output:
Catch!
Error (R1) : Cann't divide by zero !
31.2 Eval() Function
We can execute code during the runtime from string using the Eval() function
Syntax:
167

Eval(cCode)
Example:
Eval("nOutput = 5+2*5 " )
See "5+2*5 = " + nOutput + nl
Eval("for x = 1 to 10 see x + nl next")
Eval("func test see 'message from test!' ")
test()
Output:
5+2*5 = 15
1
2
3
4
5
6
7
8
9
10
message from test!
31.3 Raise() Function
We can raise an exception using the Raise() function
Syntax:
Raise(cErrorMessage)
The function will display the error message then end the execution of the program.
We can use Try/Catch/Done to avoid exceptions generated by raise() function.
Example:
nMode = 10
if nMode < 0 or nMode > 5
raise("Error : nMode not in the range 1:4")
ok
Output:
Line 4 Error : nMode not in the range 1:4
In raise in file testsraise.ring
Example:
try
testmode(6)
catch
see "avoid raise!"
done
testmode(-1)
31.3. Raise() Function 168

func testmode nMode
if nMode < 0 or nMode > 5
raise("Error : nMode not in the range 1:4")
ok
Output:
avoid raise!
Line 12 Error : nMode not in the range 1:4
In raise In function testmode() in file testsraise2.ring
called from line 7 in file testsraise2.ring
31.4 Assert() Function
We can use the Assert() function to test conditions before executing the code
If the test fail the program will be terminated with an error message contains the assert condition.
Syntax:
Assert( condition )
Example:
x = 10
assert( x = 10)
assert( x = 100 )
Output:
Line 3 Assertion Failed!
In assert in file testsassert.ring
31.4. Assert() Function 169

CHAPTER
THIRTYTWO
DEMO PROGRAMS
In this chapter we will see simple demo programs
• Language Shell
• Main Menu
32.1 Language Shell
We can create simple interactive programming environment using the next program
while true
see nl + "code:> "
give cCode
try
eval(cCode)
catch
see cCatchError
done
end
Output:
code:> see "hello world"
hello world
code:> for x = 1 to 10 see x + nl next
1
2
3
4
5
6
7
8
9
10
code:> func test see "Hello from test" + nl
code:> test()
Hello from test
code:> bye
170

32.2 Main Menu
Example:
# Demo Program
while true
see "
Main Menu
===========
[1] Say Hello
[2] Sum two numbers
[3] Stars
[4] Fact
[5] Exit
" give nMenu see nl
# we can use Switch-ON-Other-OFF instead of IF-BUT-ELSE-OK
Switch nMenu
On 1 sayhello()
On 2 Sum()
On 3 Stars()
On 4
see "Enter Number : " give x
see "Output : "
Try
see Fact(number(x))
Catch
see "Error in parameters!" + nl
Done
On "5" return
Other see "bad option" + nl
Off
end
func sayhello
see "Enter your name ? " give fname
see "Hello " + fname + nl
func sum
see "number 1 : " give num1 see "number 2 : " give num2
see "Sum : " see 0 + num1 + num2
func stars
for x = 1 to 10
see space(8)
for y = 1 to x see "*" next see nl
next
func fact x if x = 1 return 1 else return x * fact(x-1) ok
32.2. Main Menu 171

func space x y = "" for t=1 to x y += " " next return y
Output:
Main Menu
===========
[1] Say Hello
[2] Sum two numbers
[3] Stars
[4] Fact
[5] Exit
1
Enter your name ? Mahmoud Fayed
Hello Mahmoud Fayed
Main Menu
===========
[1] Say Hello
[2] Sum two numbers
[3] Stars
[4] Fact
[5] Exit
2
number 1 : 3
number 2 : 4
Sum : 7
Main Menu
===========
[1] Say Hello
[2] Sum two numbers
[3] Stars
[4] Fact
[5] Exit
3
*
**
***
****
*****
******
*******
********
*********
**********
Main Menu
===========
[1] Say Hello
[2] Sum two numbers
32.2. Main Menu 172

[3] Stars
[4] Fact
[5] Exit
4
Enter Number : 5
Output : 120
Main Menu
===========
[1] Say Hello
[2] Sum two numbers
[3] Stars
[4] Fact
[5] Exit
5
32.2. Main Menu 173

CHAPTER
THIRTYTHREE
ODBC FUNCTIONS
This chapter contains the ODBC functions provided by the Ring programming language.
• odbc_init()
• odbc_drivers()
• odbc_datasources()
• odbc_close()
• odbc_connect()
• odbc_disconnect()
• odbc_execute()
• odbc_colcount()
• odbc_fetch()
• odbc_getdata()
• odbc_tables()
• odbc_columns()
• odbc_autocommit()
• odbc_commit()
• odbc_rollback()
Before using the next function load the odbclib.ring library
load "odbclib.ring"
# Use ODBC functions
33.1 odbc_init() Function
We can create ODBC Handle using the odbc_init() function
Syntax:
odbc_init() ---> ODBC Handle
174

33.2 odbc_drivers() Function
We can get a list of ODBC drivers using the odbc_drivers() function
Syntax:
odbc_drivers(ODBC Handle) ---> List of Drivers
33.3 odbc_datasources() Function
We can get a list of ODBC data sources using the odbc_datasources() function
Syntax:
odbc_datasources(ODBC Handle) ---> List of Data sources
33.4 odbc_close() Function
After the end of using ODBC functions we can free resources using ODBC_Close() function
Syntax:
odbc_close(ODBC Handle)
33.5 Print List of ODBC Drivers
The next example print a list of ODBC drivers.
See "ODBC test 1" + nl
oODBC = odbc_init()
See "Drivers " + nl
see odbc_drivers(oODBC)
odbc_close(oODBC)
Output:
ODBC test 1
Drivers
Microsoft Access-Treiber (*.mdb) - SQLLevel=0
Driver do Microsoft Paradox (*.db ) - SQLLevel=0
Driver do Microsoft Excel(*.xls) - SQLLevel=0
Microsoft Text Driver (*.txt; *.csv) - SQLLevel=0
Driver da Microsoft para arquivos texto (*.txt; *.csv) - SQLLevel=0
Microsoft dBase-Treiber (*.dbf) - SQLLevel=0
SQL Server - CPTimeout=60
Microsoft Excel Driver (*.xls) - SQLLevel=0
Driver do Microsoft dBase (*.dbf) - SQLLevel=0
Microsoft Paradox-Treiber (*.db ) - SQLLevel=0
Microsoft ODBC for Oracle - CPTimeout=120
Microsoft Text-Treiber (*.txt; *.csv) - SQLLevel=0
Microsoft Excel-Treiber (*.xls) - SQLLevel=0
Microsoft Access Driver (*.mdb) - SQLLevel=0
Driver do Microsoft Access (*.mdb) - SQLLevel=0
33.2. odbc_drivers() Function 175

Microsoft Paradox Driver (*.db ) - SQLLevel=0
Microsoft dBase Driver (*.dbf) - SQLLevel=0
Microsoft Access Driver (*.mdb, *.accdb) - UsageCount=3
Microsoft Excel Driver (*.xls, *.xlsx, *.xlsm, *.xlsb) - UsageCount=3
Microsoft Access Text Driver (*.txt, *.csv) - UsageCount=3
SQL Server Native Client 10.0 - UsageCount=1
SQL Server Native Client 11.0 - UsageCount=1
Microsoft Access dBASE Driver (*.dbf, *.ndx, *.mdx) - UsageCount=3
Microsoft Access Paradox Driver (*.db) - UsageCount=3
MySQL ODBC 5.3 ANSI Driver - UsageCount=1
MySQL ODBC 5.3 Unicode Driver - UsageCount=1
ODBC Driver 11 for SQL Server - UsageCount=1
Lianja ODBC Driver - CPTimeout=60
Microsoft Visual FoxPro Driver - UsageCount=1
Microsoft Visual FoxPro-Treiber - UsageCount=1
Driver para o Microsoft Visual FoxPro - UsageCount=1
Microsoft FoxPro VFP Driver (*.dbf) - UsageCount=1
33.6 Print List of ODBC Data Sources
The next example print a list of ODBC data sources.
pODBC = odbc_init()
See "Data Sources " + nl
see odbc_datasources(pODBC)
odbc_close(pODBC)
Output:
ODBC test 2
Data Sources
Excel Files - Microsoft Excel Driver (*.xls, *.xlsx, *.xlsm, *.xlsb)
MS Access Database - Microsoft Access Driver (*.mdb, *.accdb)
Customer - Microsoft Access Driver (*.mdb)
IdCardData - Microsoft Access Driver (*.mdb)
MyProjectData2 - Microsoft Access Driver (*.mdb)
MyData - Microsoft Access Driver (*.mdb)
MonprojetData - Microsoft Access Driver (*.mdb)
dBASE Files - Microsoft Access dBASE Driver (*.dbf, *.ndx, *.mdx)
myvfpdata - Microsoft Visual FoxPro Driver
FACTORYDATA - Microsoft Access Driver (*.mdb)
TRAININGSYSDATA - Microsoft Access Driver (*.mdb)
RVCSYSDATASQLDB - SQL Server Native Client 11.0
PWCTRVCDATA - Microsoft Access Driver (*.mdb)
MyCompany - Microsoft Access Driver (*.mdb)
HCS - Microsoft Access Driver (*.mdb)
HCS2 - Microsoft Access Driver (*.mdb, *.accdb)
MyProjectData - Microsoft Access Driver (*.mdb)
Xtreme Sample Database 2008 - Microsoft Access Driver (*.mdb)
Lianja_Southwind - Lianja ODBC Driver
Visual FoxPro Database - Microsoft Visual FoxPro Driver
Visual FoxPro Tables - Microsoft Visual FoxPro Driver
33.6. Print List of ODBC Data Sources 176

33.7 odbc_connect() Function
We can connect to the database using the odbc_connect() function.
Syntax:
odbc_connect(ODBC Handle, cConnectionString)
33.8 odbc_disconnect() Function
We can close the connection to the database using the odbc_disconnect() function.
Syntax:
odbc_disconnect(ODBC Handle)
33.9 Open and Close Connection
The next example connect to the database then close the connection
pODBC = odbc_init()
See "Connect to database" + nl
see odbc_connect(pODBC,"DBQ=test.mdb;Driver={Microsoft Access Driver (*.mdb)}") + nl
See "disconnect" + nl
odbc_disconnect(pODBC)
See "Close database..." + nl
odbc_close(pODBC)
Output:
ODBC test 3
Connect to database
1
disconnect
Close database...
33.10 odbc_execute() Function
We can execute SQL Statements on the database using the odbc_execute() function.
Syntax:
odbc_execute(ODBC Handle, cSQLStatement)
33.11 odbc_colcount() Function
We can get columns count in the query result using the odbc_colcount() function.
Syntax:
33.7. odbc_connect() Function 177

odbc_colcount(ODBC Handle) ---> Columns Count as Number
33.12 odbc_fetch() Function
We can fetch a row from the query result using the odbc_fetch() function.
Syntax:
odbc_fetch(ODBC Handle)
33.13 odbc_getdata() Function
We can get column value from the fetched row using the odbc_getdata() function.
Syntax:
odbc_getdata(ODBC Handle, nColumnNumber) ---> Column Value
33.14 Execute Query and Print Result
The next example execute query then print the query result.
pODBC = odbc_init()
See "Select data" + nl
see odbc_execute(pODBC,"select * from person") + nl
nMax = odbc_colcount(pODBC)
See "Columns Count : " + nMax + nl
while odbc_fetch(pODBC)
See "Row data:" + nl
for x = 1 to nMax
see odbc_getdata(pODBC,x) + " - "
next
end
odbc_close(pODBC)
33.15 odbc_tables() Function
We can get a list of tables inside the database using the odbc_tables() function.
We can access the result of this function as we get any query result.
Syntax:
odbc_tables(ODBC Handle)
Example:
33.12. odbc_fetch() Function 178

See "ODBC test - Get Database Tables" + nl
pODBC = odbc_init()
odbc_connect(pODBC,"DBQ=test.mdb;Driver={Microsoft Access Driver (*.mdb)}") + nl
odbc_tables(pODBC) + nl
for x = 1 to nMax
see odbc_getdata(pODBC,x)
if x != nMax see " - " ok
next
See nl
end
See "Close database..."
odbc_close(pODBC)
Output:
ODBC test - Get Database Tables
Connect to database
Select data
Columns Count : 5
.test - NULL - Customer - TABLE - NULL
.test - NULL - employee - TABLE - NULL
.test - NULL - person - TABLE - NULL
.test - NULL - tel - TABLE - NULL
Close database...
33.16 odbc_columns() Function
We can get a list of columns inside the table using the odbc_columns() function.
Syntax:
odbc_columns(ODBC Handle, cTableName)
Example:
See "ODBC test - Get Table Columns" + nl
pODBC = odbc_init()
odbc_connect(pODBC,"DBQ=test.mdb;Driver={Microsoft Access Driver (*.mdb)}") + nl
See "Get Columns inside the Person Table" + nl
odbc_columns(pODBC,"person") + nl
see odbc_getdata(pODBC,4) + nl
end
odbc_close(pODBC)
Output:
33.16. odbc_columns() Function 179

ODBC test - Get Table Columns
Connect to database
Get Columns inside the Person Table
FIRST
LAST
STREET
CITY
STATE
ZIP
HIREDATE
MARRIED
AGE
SALARY
NOTES
Close database...
33.17 odbc_autocommit() Function
We can enable or disable the auto commit feature using the odbc_autocommit() function.
Syntax:
odbc_autocommit(ODBC Handle, lStatus) # lStatus can be True or False
33.18 odbc_commit() Function
We can commit updates to the database using the odbc_commit() function.
Syntax:
odbc_commit(ODBC Handle)
33.19 odbc_rollback() Function
We can rollback updates to the database using the odbc_rollback() function.
Syntax:
odbc_rollback(ODBC Handle)
33.20 Transactions and Using Commit and Rollback
Example:
See "ODBC Test - Transactions and using Commit and Rollback" + nl
pODBC = odbc_init()
see "insert data..." + nl
odbc_autocommit(pODBC,0)
33.17. odbc_autocommit() Function 180

for x = 1 to 10000
odbc_execute(pODBC,"insert into tel values (" + x + ",'mahmoud')")
next
for x = 10001 to 15000
odbc_execute(pODBC,"insert into tel values (" + x + ",'samir')")
next
odbc_commit(pODBC)
for x = 15001 to 20000
odbc_execute(pODBC,"insert into tel values (" + x + ",'fayed')")
next
ODBC_ROLLBACK(pODBC)
odbc_execute(pODBC,"insert into tel values (" + x + ",'fayed')")
odbc_commit(pODBC)
odbc_close(pODBC)
Output:
ODBC Test - Transactions and using Commit and Rollback
Connect to database
1
insert data...
Close database...
33.21 Save and Restore images
The next example save an image inside the database
See "ODBC test - Save image in the database" + nl
pODBC = odbc_init()
see "Read Image File..." + nl
cFile = str2hex(read("testsmahmoud.jpg"))
see "size " + len(CFile)+nl
see "Save image in the database..." + nl
stmt = "insert into tel values (20000,'mahmoud','" + cFile + "');"
odbc_execute(pODBC,stmt)
odbc_close(pODBC)
The next example restore the image from the database
See "ODBC Test - Restore image from the database" + nl
pODBC = odbc_init()
see odbc_execute(pODBC,"select * from tel") + nl
33.21. Save and Restore images 181

See "Write image file" + nl
write("testsgreat.jpg",hex2str( odbc_getdata(pODBC,3) ) )
end
odbc_close(pODBC)
33.21. Save and Restore images 182

CHAPTER
THIRTYFOUR
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
34.1 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()
183

Output:
MySQL Client Version : 6.1.5
34.2 MySQL_Init() Function
We can start using MySQL Client through the MySQL_Init() function.
Syntax:
MySQL_Init() ---> MySQL Handle
34.3 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
34.4 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
34.5 MySQL_Close() Function
We can close the connection to the MySQL database using the MySQL_Close() function
Syntax:
MySQL_Close(MySQL Handle)
34.6 MySQL_Query() Function
We can execute SQL queries using the MySQL_Query() function
Syntax:
MySQL_Query(MySQL Handle, cSQLQuery)
34.2. MySQL_Init() Function 184

34.7 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
34.8 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)")
if mysql_query(con, "INSERT INTO Employee VALUES(2,'Samir',16000)")
if mysql_query(con, "INSERT INTO Employee VALUES(3,'Fayed',17000)")
34.7. Create Database 185

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
34.9 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')")
mysql_query(con, "INSERT INTO Customers(Name) VALUES('Samir')")
mysql_query(con, "INSERT INTO Customers(Name) VALUES('Fayed')")
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
34.9. MySQL_Insert_ID() Function 186

34.10 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
34.11 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)
34.12 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
34.13 MySQL_Columns() Function
We can get a list of columns names using the MySQL_Columns() function.
Syntax:
34.10. MySQL_Result() Function 187

The Ring programming language version 1.4.1 book - Part 7 of 31

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The Ring programming language version 1.4.1 book - Part 7 of 31