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A lot of places I saw people asking for ways to generate Insert statements. We do have GUI Tools which can extract insert statements for us readily. Most of the time I choose the MySQLDump way to generate insert statements. mysqldump -uroot -ppassword –complete-insert –no-create-info DATABASE TABLENAME > TABLENAME.sql But mind is very unstable and hungry, we don’t stop [...] Related posts:

1. Stored procedure to add-remove prefix by rename table mysql
2. Stored procedure to Find database objects
3. MySQL Stored procedure – Split Delimited string into Rows

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+-----------+
| RESULT    |
+-----------+
| 0x199c610 |
+-----------+
1 row in set (0 sec)

+--------+
| result |
+--------+
| done   |
+--------+
1 row in set (0.01 sec)

+--------------+
| result       |
+--------------+
| Hello World! |
+--------------+
1 row in set (0.01 sec)

+--------+
| result |
+--------+
| done   |
+--------+
1 row in set (0 sec)

PlanetMySQL Voting: Vote UP / Vote DOWN

+-----------+
| RESULT    |
+-----------+
| 0x199c610 |
+-----------+
1 row in set (0 sec)

+--------+
| result |
+--------+
| done   |
+--------+
1 row in set (0.01 sec)

+--------------+
| result       |
+--------------+
| Hello World! |
+--------------+
1 row in set (0.01 sec)

+--------+
| result |
+--------+
| done   |
+--------+
1 row in set (0 sec)

PlanetMySQL Voting: Vote UP / Vote DOWN

Previously, in “Thoughts on Thoughts on Drizzle” I theorized that one of the major reasons why we did not see lots of people jumping at stored procedures in MySQL was that it wasn’t in their native language (for lack of a better term). We’ve seen External Language Stored Procedures for MySQL that let you write stored procedures in some other languages…. but I felt something was missing.

Firstly, I wanted a language I was really familiar with and comfortable writing complex things in.

Secondly, it should be compiled so that it runs as fast as possible.

Thirdly, it shouldn’t just be linking to a pre-compiled library (drizzle function plugins do that already)

So… the obvious choice was C.

I have a really, really, really early prototype:

drizzle> SELECT LIBTCC("int foo(char* s) { s[0]='4'; s[1]='2'; s[2]=0; return 2; }") AS RESULT;


+--------+
| RESULT |
+--------+
| 42     |
+--------+
1 row in set (0 sec)

or… a bit more sophisticated:

drizzle> SELECT LIBTCC("#include <string.h>\nint foo(char* s) { strcpy(s,\"Hello World!\");; return strlen(s); }") AS RESULT;


+--------------+
| RESULT       |
+--------------+
| Hello World! |
+--------------+
1 row in set (0 sec)

I’m using a function as a bit of a cheat… but the string is passed to libtcc (modified so it’s a shared library so I can load it into drizzle), where it is compiled into native object code (in my case x86-64) and then run.

With the right bits of foo… I could allow calling of all sorts of server functions…. such as those to execute SQL inside the current transaction context.

There are a number of reasons why this is Pure Evil(TM):

• It executes inside the address space of your database server
  one null pointer dereference and your database server is all gone.
• It’s arbitrary code injection by design
  Exactly how insane are you? Security–;
• While great for me and my C hacking friends, possibly not for web app developers, who likely aren’t writing their apps in C every day.
• See the first reason. Is that not reason enough? Memory protection is a good thing yo.

Anyway, you can see the code up on launchpad in the drizzle-libtcc-function branch. You’ll need to modify your tcc source so that the Makefile snippet for libtcc.o looks like this:

# libtcc generation and test
libtcc.o: $(NATIVE_FILES)
        $(CC) -fPIC -o $@ -c libtcc.c $(NATIVE_TARGET) $(CFLAGS)

libtcc.a: libtcc.o
        $(AR) rcs $@ $^

libtcc.so: libtcc.o
        $(CC) -shared -Wl,-soname,libtcc.so.1 -o $@ libtcc.o

PlanetMySQL Voting: Vote UP / Vote DOWN

Previously, in “Thoughts on Thoughts on Drizzle” I theorized that one of the major reasons why we did not see lots of people jumping at stored procedures in MySQL was that it wasn’t in their native language (for lack of a better term). We’ve seen External Language Stored Procedures for MySQL that let you write stored procedures in some other languages…. but I felt something was missing.

Firstly, I wanted a language I was really familiar with and comfortable writing complex things in.

Secondly, it should be compiled so that it runs as fast as possible.

Thirdly, it shouldn’t just be linking to a pre-compiled library (drizzle function plugins do that already)

So… the obvious choice was C.

I have a really, really, really early prototype:

drizzle> SELECT LIBTCC("int foo(char* s) { s[0]='4'; s[1]='2'; s[2]=0; return 2; }") AS RESULT;


+--------+
| RESULT |
+--------+
| 42     |
+--------+
1 row in set (0 sec)

or… a bit more sophisticated:

drizzle> SELECT LIBTCC("#include <string.h>\nint foo(char* s) { strcpy(s,\"Hello World!\");; return strlen(s); }") AS RESULT;


+--------------+
| RESULT       |
+--------------+
| Hello World! |
+--------------+
1 row in set (0 sec)

I’m using a function as a bit of a cheat… but the string is passed to libtcc (modified so it’s a shared library so I can load it into drizzle), where it is compiled into native object code (in my case x86-64) and then run.

With the right bits of foo… I could allow calling of all sorts of server functions…. such as those to execute SQL inside the current transaction context.

There are a number of reasons why this is Pure Evil(TM):

• It executes inside the address space of your database server
  one null pointer dereference and your database server is all gone.
• It’s arbitrary code injection by design
  Exactly how insane are you? Security–;
• While great for me and my C hacking friends, possibly not for web app developers, who likely aren’t writing their apps in C every day.
• See the first reason. Is that not reason enough? Memory protection is a good thing yo.

Anyway, you can see the code up on launchpad in the drizzle-libtcc-function branch. You’ll need to modify your tcc source so that the Makefile snippet for libtcc.o looks like this:

# libtcc generation and test
libtcc.o: $(NATIVE_FILES)
        $(CC) -fPIC -o $@ -c libtcc.c $(NATIVE_TARGET) $(CFLAGS)

libtcc.a: libtcc.o
        $(AR) rcs $@ $^

libtcc.so: libtcc.o
        $(CC) -shared -Wl,-soname,libtcc.so.1 -o $@ libtcc.o

PlanetMySQL Voting: Vote UP / Vote DOWN

Here is one more procedure – (this time) for mass renaming of table. Adding and Removing table-name prefixes A friend of mine was renaming 100+ tables by using replace methods in notepad. I showed em a bit better editor: Editplus and then I thought of rescue rest of those who are still interested in some [...] Related posts:

1. Stored procedure – Execute query if table or Column exists
2. Stored procedure to Find database objects
3. MySQL Stored procedure – Split Delimited string into Rows

PlanetMySQL Voting: Vote UP / Vote DOWN

It has been more than a year since my self-imposed hiatus from serious MySQL development started and I think it is about time that I get back into the saddle. I have a handful of working prototypes but I should get the code out there, back into the community.I learned a bunch of stuff during the past year at Google but in the end, working on JavaScript, HTML/CSS and Google proprietary languages
PlanetMySQL Voting: Vote UP / Vote DOWN