Update README.md

Author: almgwary

README.md

@@ -1,2 +1,246 @@
-# oracle-migration-mysql
-migrate oracle row into MySQL insert statements
+# Oracle Migration Mysql
+Migrate oracle row into MySQL insert statements as offline files
+
+
+``` sql
+
+-- The following script export some ORACLE tables into SQL insert statments 
+-- It use MIGRATION_COLUMNS_SETTINGS, MIGRATION_TABELS_LIST table to change the columns names
+
+BEGIN 
+  DBMS_OUTPUT.PUT_LINE('STARTING');
+END; 
+
+/
+-- Check if MIGRATION_COLUMNS_SETTINGS table exits or create it
+DECLARE
+nCount NUMBER;
+v_sql LONG;
+
+BEGIN
+--DBMS_OUTPUT.PUT_LINE('Check MIGRATION_COLUMNS_SETTINGS table exists?');
+SELECT count(*) into nCount FROM dba_tables where table_name = 'MIGRATION_COLUMNS_SETTINGS';
+IF(nCount <= 0)
+THEN
+--  DBMS_OUTPUT.PUT_LINE('No, MIGRATION_COLUMNS_SETTINGS table not exists, Creating new one...');
+  v_sql:='
+  create table MIGRATION_COLUMNS_SETTINGS
+  (
+  ID NUMBER(3),
+  TABLE_NAME VARCHAR2(30) NOT NULL,
+  OLD_COLUMN_NAME VARCHAR2(30) NOT NULL,
+  NEW_COLUMN_NAME VARCHAR2(30) NOT NULL
+  )';
+  execute immediate v_sql;
+--ELSE
+--DBMS_OUTPUT.PUT_LINE('Yes MIGRATION_COLUMNS_SETTINGS table  exists.');
+END IF;
+
+END;
+
+
+
+--declare 
+--  fHandle  UTL_FILE.FILE_TYPE;
+--begin
+--  fHandle := UTL_FILE.FOPEN('my_directory', 'test_file', 'w');
+--
+--  UTL_FILE.PUT(fHandle, 'This is the first line');
+--  UTL_FILE.PUT(fHandle, 'This is the second line');
+--  UTL_FILE.PUT_LINE(fHandle, 'This is the third line');
+--
+--  UTL_FILE.FCLOSE(fHandle);
+--EXCEPTION
+--  WHEN OTHERS THEN
+--    DBMS_OUTPUT.PUT_LINE('Exception: SQLCODE=' || SQLCODE || '  SQLERRM=' || SQLERRM);
+--    RAISE;
+--end;
+
+
+/
+-- Check if MIGRATION_TABELS_LIST table exits or create it
+DECLARE
+nCount NUMBER;
+v_sql LONG;
+
+BEGIN
+--DBMS_OUTPUT.PUT_LINE('Check MIGRATION_TABELS_LIST table exists?');
+SELECT count(*) into nCount FROM dba_tables where table_name = 'MIGRATION_TABELS_LIST';
+IF(nCount <= 0)
+THEN
+--  DBMS_OUTPUT.PUT_LINE('No, MIGRATION_TABELS_LIST table not exists, Creating new one...');
+  v_sql:='
+  create table MIGRATION_TABELS_LIST
+  (
+  ID NUMBER(3),
+  TABLE_NAME VARCHAR2(30) NOT NULL
+  )';
+  execute immediate v_sql;
+--ELSE
+--DBMS_OUTPUT.PUT_LINE('Yes MIGRATION_TABELS_LIST table  exists.');
+END IF;
+
+END;
+
+
+/
+
+
+-- Create method to get new columns names
+-- GET_COLUMN_NAME is function to get new column names from MIGRATION_COLUMNS_SETTINGS table
+CREATE OR REPLACE FUNCTION  GET_COLUMN_NAME ( table_name  VARCHAR2, column_name  VARCHAR2   )
+ RETURN READ_ONLY.MIGRATION_COLUMNS_SETTINGS.NEW_COLUMN_NAME%TYPE
+  IS
+    NEW_NAME READ_ONLY.MIGRATION_COLUMNS_SETTINGS.NEW_COLUMN_NAME%TYPE;
+  BEGIN 
+--   DBMS_OUTPUT.PUT_LINE('START SELECTING table_name:' || table_name || ' column_name:' || column_name );
+    SELECT NEW_COLUMN_NAME
+      INTO NEW_NAME
+      FROM READ_ONLY.MIGRATION_COLUMNS_SETTINGS
+      WHERE TABLE_NAME = table_name AND OLD_COLUMN_NAME = column_name;
+      
+      RETURN NEW_NAME;
+      
+      EXCEPTION
+        WHEN OTHERS  THEN
+          NEW_NAME := column_name;
+--          DBMS_OUTPUT.PUT_LINE('Error SELECTING ' || 'An error was encountered - '||SQLCODE||' -ERROR- '||SQLERRM);
+--          DBMS_OUTPUT.PUT_LINE('END SELECTING column_name:' ||  column_name || ' NEW_NAME:' || NEW_NAME );
+          NEW_NAME := column_name;
+          RETURN NEW_NAME;
+   
+END GET_COLUMN_NAME;
+ 
+/
+
+
+-- create path for migration
+
+create or replace directory temp_dir as './your/path/here';
+/
+grant read, write on directory temp_dir to PUBLIC
+/
+
+-- Start migration
+DECLARE
+  cur SYS_REFCURSOR;
+  curid NUMBER;
+  desctab DBMS_SQL.desc_tab;
+  colcnt NUMBER;
+  namevar VARCHAR2(4000);
+  numvar NUMBER;
+  datevar DATE;
+  total_row_fetched number:=0;
+  file_name varchar(50):='';
+  out_columns varchar2(10000);
+  out_values varchar2(10000);
+  fHandle  UTL_FILE.FILE_TYPE;
+  batch_file_number NUMBER := 1;
+  
+BEGIN
+
+  --  fHandle := UTL_FILE.FOPEN('temp_dir', 'out.sql', 'w');
+  -- write to file with name 
+  --  fHandle := UTL_FILE.FOPEN('temp_dir', 'out'|| TO_CHAR(sysdate, 'yyyy-mm-dd hh:mm' )||'-part-'|| batch_file_number ||'.sql', 'w');
+  -- get list of tabels to log 
+  FOR rec IN (SELECT TABLE_NAME 
+                FROM MIGRATION_TABELS_LIST 
+               ORDER BY TABLE_NAME)
+  LOOP
+    OPEN cur FOR 'SELECT * FROM '||rec.TABLE_NAME||' ORDER BY 1';
+    DBMS_OUTPUT.put_line('Working on table:' ||rec.TABLE_NAME);
+    
+    
+    
+    
+    
+    
+    curid := DBMS_SQL.to_cursor_number(cur);
+    DBMS_SQL.describe_columns(curid, colcnt, desctab);
+
+    out_columns := 'INSERT INTO '||rec.TABLE_NAME||'(';
+    
+
+
+
+    
+    FOR indx IN 1 .. colcnt LOOP
+    
+      -- get table name and column name, check if they are exist in the MIGRATION_COLUMNS_SETTINGS
+      -- if it exists get the new name, else use current name
+      out_columns := out_columns||READ_ONLY.GET_COLUMN_NAME( rec.TABLE_NAME , desctab(indx).col_name )||',';
+      IF desctab (indx).col_type = 2 
+      THEN
+        DBMS_SQL.define_column (curid, indx, numvar); 
+      ELSIF desctab (indx).col_type = 12
+      THEN
+        DBMS_SQL.define_column (curid, indx, datevar); 
+      ELSE
+        DBMS_SQL.define_column (curid, indx, namevar, 4000); 
+      END IF;
+    END LOOP;
+
+    out_columns := rtrim(out_columns,',')||') VALUES (';
+
+    WHILE DBMS_SQL.fetch_rows (curid) > 0 
+    LOOP
+      out_values := '';
+      FOR indx IN 1 .. colcnt 
+      LOOP
+        IF (desctab (indx).col_type = 1) 
+        THEN
+          DBMS_SQL.COLUMN_VALUE (curid, indx, namevar);
+          out_values := out_values||''''||namevar||''',';
+        ELSIF (desctab (indx).col_type = 2)
+        THEN
+          DBMS_SQL.COLUMN_VALUE (curid, indx, numvar);
+          out_values := out_values||numvar||',';
+        ELSIF (desctab (indx).col_type = 12)
+        THEN
+          DBMS_SQL.COLUMN_VALUE (curid, indx, datevar);
+          out_values := out_values||
+            'to_date('''||to_char(datevar,'DD.MM.YYYY HH24:MI:SS')||
+             ''',''DD.MM.YYYY HH24:MI:SS''),';
+        END IF;
+      END LOOP; 
+     DBMS_OUTPUT.put_line(out_columns||rtrim(out_values,',')||');');
+     -- create new file for each 2M record
+    -- write to file with name 
+    if mod ( total_row_fetched, 2 ) = 0 then
+      /* close old file, open new */
+      -- if file open close it
+      if SYS.UTL_FILE.IS_OPEN(fHandle)then
+       UTL_FILE.FCLOSE(fHandle);
+      end if;
+       
+       
+       file_name := 'out-'|| TO_CHAR(sysdate, 'yyyy-mm-dd-hh:mm' )||'-part-'|| batch_file_number ||'.sql';
+       batch_file_number := batch_file_number + 1;
+       fHandle := UTL_FILE.FOPEN('temp_dir',file_name , 'w');
+       DBMS_OUTPUT.put_line('file: ' ||file_name );
+       DBMS_OUTPUT.put_line('total_row_fetched: ' || total_row_fetched);
+       
+    end if;
+    total_row_fetched := total_row_fetched + 1;
+    -- write to file
+    UTL_FILE.PUT_LINE(fHandle, out_columns||rtrim(out_values,',')||');');
+ 
+
+    END LOOP;
+
+    DBMS_SQL.close_cursor (curid);
+
+  END LOOP;
+  UTL_FILE.FCLOSE(fHandle);
+  DBMS_OUTPUT.put_line('FINISHED');
+  EXCEPTION
+  WHEN OTHERS THEN
+    DBMS_OUTPUT.PUT_LINE('Exception: SQLCODE=' || SQLCODE || '  SQLERRM=' || SQLERRM);
+    RAISE;
+END;
+/
+ 
+ 
+
+
+```