What is Pro * C/C ++, embedded SQL, the first pro * c program, pro * c ++, Makefile, Proc addition, deletion, modification, and query, and makefileproc?

[Switch] what is Pro * C/C ++, embedded SQL, the first pro * c program, pro * c ++, Makefile, Proc addition, deletion, modification, and query, makefileproc

1. What is Pro * C/C ++?

1. applications developed by embedding SQL statements in the process Programming Language C/C ++

2. What is embedded SQL?

1. SQL used in general programming languages is called embedded SQL

2. Embedded SQL statements in many Chinese languages are defined in the SQL standard.

3. Different vendors have different implementations for Embedded SQL

3. What is Pro * C/C ++?

1. An application developed by embedding SQL statements in C/C ++.

2. Objective: To make the efficiency Language c/c ++ known as a database access tool.

4. The carrier of Embedded SQL is the host language.

Host language Pro Program C/C ++ Pro * C/C ++ FORTRAN Pro * FORTRAN PASCAL Pro * PASCAL COBOL Pro * COBOL PL/I Pro * PL/I Ada Pro * Ada

5. database access methods

(1) use SQL * Plus, which has SQL commands to access the database through interactive applications;

(2) applications developed by application development tools in the fourth generation language access the database. These tools include SQL * Froms, QL * Reportwriter, and SQL * Menu. (3) access using SQL language or ORACLE database functions embedded in the third generation language. How to access the oracle database.

Others:

6. The first pro * C program

When developing the pro * c program, A needs to configure pcscfg. cfg under/home/oracle_11/app/oracle/product/11.2.0/db_1/precomp/admin.

The above configuration is correct.

B. Create dm01_hello.pc.

The file content is as follows:

Dependent header file: /Home/oracle_11/app/oracle/product/11.2.0/db_1/precomp/public SQLCA. H

Dm01_hello.pc file content (use the UE tool to save and upload the content to the server through FTP)

# Include <stdio. h> # Include <string. h> # Include "sqlca. h" // Define the host variable serverid Exec SQL BEGIN DECLARE SECTION; // Format: User Name/user password @ server name Char * serverid = "scott/123456 @ orcl "; Exec SQL END DECLARE SECTION; Int main () { Int ret = 0; Printf ("hello... \ n "); // Host variable in C Printf ("serverid: % s \ n", serverid ); // The embedded SQL language must start with EXEC SQL // Add serverid to indicate that this variable is used. Exec SQL connect: serverid; If (sqlca. sqlcode! = 0) { Ret = sqlca. sqlcode; Printf ("exec SQL connect: err, % d \ n", ret ); Return ret; } Printf ("connect OK \ n "); Return ret; }

Compile and run the dm01_hello.pc command: proc dm01_hello.pc Then generate the. out file. Note that error 1: The cause of the above error is that the shared library is not introduced and should be executed as follows: Gcc dm01_hello.c-o dm01_hello-I/home/oracle_11/app/oracle/product/11.2.0/db_1/precomp/public-L/home/oracle_11/app/oracle/product/11.2.0/ db_1/lib-lclntsh The above is the introduction of the shared library clntsh. so. Note Error 2: [Oracle @ localhost day03] $./dm01_hello Hello .... Serverid: scott/123456 @ orcl Exec SQL connect: err,-12541. You can run the following command to view the error cause: Oerr ora 12541 (this error occurs because the listener is not started) At this time: Sqlplus/nolog Conn/as sysdba Startup Quit Run the following command: Lsnrctl start (you can use the ps-u oracle command to view oracle-related startup services) No errors will occur during the execution.

7 PreCompile compiler precompiled Program

1. Where is the tool?

Function: converts a Pro * c source program to a pure C source program.

Basic command format: Proc iname = filename [OptionName1 = value1]… [OptionNameN = valueN] Common compilation options: INAME = path and filename (name of the input file) ONAME = path and filename (name of the output file) INCLUDE = path (path of the header file) -- INCLUDE = path name or INCLUDE = (path name 1, path name 2) PARSE = FULL | PARTIA | NONE (default FULL for C, Others for C ++) If You Want To compile c ++, change it to PARTIA or NONE. CODE = ANSI_C | CPP (default ansi_c) USERID = username/password

8. compile c ++ files using proc

By default, proc compiles the. c file. To compile a c ++ file, perform the following operations:

Proc iname =./dm02_hello.pconame = dm02_hello.cc PARSE = none code = CPP

# Include <iostream> # Include <stdio. h> # Include <string. h> # Include "sqlca. h" Using namespace std; // Define the host variable serverid Exec SQL BEGIN DECLARE SECTION; Char * serverid = "scott/123456 @ orcl "; Exec SQL END DECLARE SECTION; Int main () { Int ret = 0; Cout <"hello..." <endl; // Host variable in C Printf ("serverid: % s \ n", serverid ); // The embedded SQL language must start with EXEC SQL // When serverid is used to reference serverid, use: Exec SQL connect: serverid; If (sqlca. sqlcode! = 0) { Ret = sqlca. sqlcode; Printf ("exec SQL connect: err, % d \ n", ret ); Return ret; } Printf ("connect OK \ n "); Return ret; }

Run the following command: Proc iname =./dm02_hello.pc oname = dm02_hello.cc PARSE = none code = CPP Execution result: Note that the preceding red lines and executed C are different.

Then compile the cc file: G ++ dm02_hello.cc-o dm02_hello-I/home/oracle_11/app/oracle/product/11.2.0/db_1/precomp/public-L/home/oracle_11/app/oracle/product/ 11.2.0/db_1/lib-lclntsh

9. Write the simplest MakeFile

All: dm01_hello dm02_hello Dm01_hello: @ Echo 'proc dm01_hello in in' Proc dm01_hello.pc @ Echo 'gcc dm01_hello in in' Gcc dm01_hello.c-o dm01_hello-I $ {ORACLE_HOME}/precomp/public-L $ {ORACLE_HOME}/lib-lclntsh Dm02_hello: @ Echo 'proc dm02_hello in in' Proc iname =./dm02_hello.pc oname = dm02_hello.cc PARSE = none code = CPP @ Echo 'gcc dm02_hello in in' G ++ dm02_hello.cc-o dm02_hello-I $ {ORACLE_HOME}/precomp/public-L $ {ORACLE_HOME}/lib-lclntsh Clean: @ Rm dm01_hello @ Rm dm02_hello

Run the following command: Make

10 add, delete, modify, and query databases:

Compile a public Makefile

All: dm01_dbop Dm01_dbop: @ Echo 'proc dm01_dbop in in' Proc dm01_dbop.pc @ Echo 'gcc dm01_dbop in in' Gcc dm01_dbop.c-o dm01_dbop-I $ {ORACLE_HOME}/precomp/public-L $ {ORACLE_HOME}/lib-lclntsh Clean: @ Rm dm01_dbop

Insert data:

# Include <stdio. h> # Include <string. h> # Include <string. h> # Include "sqlca. h" // Define the host variable serverid Exec SQL BEGIN DECLARE SECTION; Char * serverid = "scott/tiger @ orcl "; Int deptno; Char dname [20]; Char loc [20]; Int deptno2; Char dname2 [20]; Char loc2 [20]; Exec SQL END DECLARE SECTION; Int main () { Int ret = 0; Printf ("hello... \ n "); // Host variable in C Printf ("serverid: % s \ n", serverid ); // The embedded SQL language must start with EXEC SQL // Serverid Exec SQL connect: serverid; If (sqlca. sqlcode! = 0) { Ret = sqlca. sqlcode; Printf ("exec SQL connect: err, % d \ n", ret ); Return ret; } Printf ("connect OK \ n "); Deptno = 50; Strcpy (dname, "50 name "); Strcpy (loc, "50loc "); // Add data Exec SQL insert into dept (deptno, dname, loc) values (: deptno,: dname,: loc ); Exec SQL commit;   Exec SQL COMMIT RELEASE; // submit a transaction to disconnect Return ret; }

Running result:

Delete

Makefile omitted

# Include <stdio. h> # Include <string. h> # Include <string. h> # Include "sqlca. h" // Define the host variable serverid Exec SQL BEGIN DECLARE SECTION; Char * serverid = "scott/tiger @ orcl "; Int deptno; Char dname [20]; Char loc [20]; Int deptno2; Char dname2 [20]; Char loc2 [20]; Exec SQL END DECLARE SECTION; Int main () { Int ret = 0; Printf ("hello... \ n "); // Host variable in C Printf ("serverid: % s \ n", serverid ); // The embedded SQL language must start with EXEC SQL // Serverid Exec SQL connect: serverid; If (sqlca. sqlcode! = 0) { Ret = sqlca. sqlcode; Printf ("exec SQL connect: err, % d \ n", ret ); Return ret; } Printf ("connect OK \ n "); Deptno = 50; Strcpy (dname, "50 name "); Strcpy (loc, "50loc ");   Exec SQL delete from dept where deptno =: deptno; Exec SQL commit; Exec SQL COMMIT RELEASE; // submit a transaction to disconnect Return ret; }

Running result:

Update:

Makefile

# Include <stdio. h> # Include <string. h> # Include <string. h> # Include "sqlca. h" // Define the host variable serverid Exec SQL BEGIN DECLARE SECTION; Char * serverid = "scott/tiger @ orcl "; Int deptno; Char dname [20]; Char loc [20];   Int deptno2; Char dname2 [20]; Char loc2 [20]; Exec SQL END DECLARE SECTION;   // Update Int main () { Int ret = 0; Printf ("hello... \ n "); // Host variable in C Printf ("serverid: % s \ n", serverid ); // The embedded SQL language must start with EXEC SQL // Serverid Exec SQL connect: serverid; If (sqlca. sqlcode! = 0) { Ret = sqlca. sqlcode; Printf ("exec SQL connect: err, % d \ n", ret ); Return ret; } Printf ("connect OK \ n "); Deptno = 50; Strcpy (dname, "50 name "); Strcpy (loc, "50loc "); // Add data Exec SQL insert into dept (deptno, dname, loc) values (: deptno,: dname,: loc ); Exec SQL commit; Printf ("enter key... update \ n "); Getchar (); Getchar (); Strcpy (loc, "50 locloc "); Exec SQL update dept set loc =: loc where deptno =: deptno; // Exec SQL delete from dept where deptno =: deptno; Exec SQL COMMIT RELEASE; // submit a transaction to disconnect Return ret; }

Execution result: Database results:

Query and display results:

# Include <stdio. h> # Include <string. h> # Include <string. h> # Include "sqlca. h" // Define the host variable serverid Exec SQL BEGIN DECLARE SECTION; Char * serverid = "scott/123456 @ orcl "; Int deptno; Char dname [20]; Char loc [20]; Int deptno2; Char dname2 [20]; Char loc2 [20]; Exec SQL END DECLARE SECTION; // Obtain Int main () { Int ret = 0; Printf ("hello... \ n "); // Host variable in C Printf ("serverid: % s \ n", serverid ); // The embedded SQL language must start with EXEC SQL // Serverid Exec SQL connect: serverid; If (sqlca. sqlcode! = 0) { Ret = sqlca. sqlcode; Printf ("exec SQL connect: err, % d \ n", ret ); Return ret; } Printf ("connect OK \ n "); Deptno = 50; Strcpy (dname, "50 name "); Strcpy (loc, "50loc "); Exec SQL select deptno, dname, loc into: deptno2,: dname2,: loc2 from dept where deptno =: deptno;   Printf ("% d, % s, % s \ n", deptno2, dname2, loc2 );   Exec SQL COMMIT RELEASE; // submit a transaction to disconnect   Return ret; }

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