[Monetdb-developers] about MAL optimize

newer
[Monetdb-developers] Merge Tables...

kun ren

11 Aug 2010 11 Aug '10

7:25 a.m.

Dear everyone, Recently,I am intersting in MAL optimize，and have read the manual of the MAL optimize, but it is so long, Possible if we want to use mal optimize ,we must degignation the optimize consideration, such as alias removal, constant expression,join path optimizer;And then I dedug the MonetDB,but default it don't use any optimize.so what do you think about the mal optimize? Best regards.

Attachments:

attachment.html (text/html — 563 bytes)

Show replies by date

Fabian Groffen

11 Aug 11 Aug

7:42 a.m.

On 11-08-2010 15:25:15 +0800, kun ren wrote:

...

Recently,I am intersting in MAL optimize，and have read the manual of the MAL optimize, but it is so long, Possible if we want to use mal optimize ,we must degignation the optimize consideration, such as alias removal, constant expression,join path optimizer;And then I dedug the MonetDB,but default it don't use any optimize.so what do you think about the mal optimize?

It is only used when you use SQL. The sql_optimizer setting in monetdb5.conf controls which optimisers are run, which by default are quite a few.

kun ren

7:49 a.m.

It is only used by SQL? and how to designation the optimiser？but when I write MAL,for example, i:=0; b:= "done"; barrier go:= true; c:=i+1; d:="step"; v:=d; io.print(v); i:=c; redo go:= i<2; exit go; io.print(b); optimizer.aliasRemoval(); the last optimizer.aliasRemoval() is used for optimizing? 2010/8/11 Fabian Groffen

...

...
Recently,I am intersting in MAL optimize，and have read the manual of

On 11-08-2010 15:25:15 +0800, kun ren wrote: the

...
MAL optimize, but it is so long, Possible if we want to use mal optimize ,we must degignation the optimize consideration, such as alias removal, constant expression,join path optimizer;And then I dedug the MonetDB,but default it don't use any optimize.so what do you think about the mal optimize?

It is only used when you use SQL. The sql_optimizer setting in monetdb5.conf controls which optimisers are run, which by default are quite a few.

------------------------------------------------------------------------------ This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

Stefan Manegold

8:15 a.m.

Yes, if you write MAL "by hand" (or have some program create it) that does explicitly call a MAL optimizer, that MAL optimizer is indeed used to optimize the MAL code according to its very purpose. Stefan On Wed, Aug 11, 2010 at 03:49:47PM +0800, kun ren wrote:

...

It is only used by SQL? and how to designation the optimiser？but when I write MAL,for example, i:=0; b:= "done"; barrier go:= true; c:=i+1; d:="step"; v:=d; io.print(v); i:=c; redo go:= i<2; exit go; io.print(b); optimizer.aliasRemoval();

the last optimizer.aliasRemoval() is used for optimizing?

2010/8/11 Fabian Groffen

...
...
Recently,I am intersting in MAL optimize，and have read the manual of

On 11-08-2010 15:25:15 +0800, kun ren wrote: the

...
MAL optimize, but it is so long, Possible if we want to use mal optimize ,we must degignation the optimize consideration, such as alias removal, constant expression,join path optimizer;And then I dedug the MonetDB,but default it don't use any optimize.so what do you think about the mal optimize?

It is only used when you use SQL. The sql_optimizer setting in monetdb5.conf controls which optimisers are run, which by default are quite a few.

------------------------------------------------------------------------------ This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

...

------------------------------------------------------------------------------ This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev

...

_______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

kun ren

8:23 a.m.

I read sql_optimizer setting in monetdb5.conf ,and default setting is: sql_optimizer=default_pipe default_pipe=inline,remap,evaluate,costModel,coercions,emptySet,aliases,mitosis,mergetable,deadcode,commonTerms,joinPath,reorder,deadcode,reduce,garbageCollector,dataflow,history,multiplex so there are many optimizer,but why when i debug MonetDB,and dump the mal of my sql statement,but i can't find the optimizer mal ,and don't enter the optimizer? like there are no optimizer, 2010/8/11 Stefan Manegold

...

Yes, if you write MAL "by hand" (or have some program create it) that does explicitly call a MAL optimizer, that MAL optimizer is indeed used to optimize the MAL code according to its very purpose.

Stefan

On Wed, Aug 11, 2010 at 03:49:47PM +0800, kun ren wrote:

...
It is only used by SQL? and how to designation the optimiser？but when I write MAL,for example, i:=0; b:= "done"; barrier go:= true; c:=i+1; d:="step"; v:=d; io.print(v); i:=c; redo go:= i<2; exit go; io.print(b); optimizer.aliasRemoval();

the last optimizer.aliasRemoval() is used for optimizing?

2010/8/11 Fabian Groffen

...
...
Recently,I am intersting in MAL optimize，and have read the manual of

On 11-08-2010 15:25:15 +0800, kun ren wrote: the

...
MAL optimize, but it is so long, Possible if we want to use mal optimize ,we must degignation the optimize consideration, such as alias removal, constant expression,join path optimizer;And then I dedug the MonetDB,but default it don't use any optimize.so what do you think about the mal optimize?

It is only used when you use SQL. The sql_optimizer setting in monetdb5.conf controls which optimisers are run, which by default are quite a few.

...
...
This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

...
------------------------------------------------------------------------------

...
This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev

...
_______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

Stefan Manegold

8:29 a.m.

On Wed, Aug 11, 2010 at 04:23:42PM +0800, kun ren wrote:

...

I read sql_optimizer setting in monetdb5.conf ,and default setting is: sql_optimizer=default_pipe default_pipe=inline,remap,evaluate,costModel,coercions,emptySet,aliases,mitosis,mergetable,deadcode,commonTerms,joinPath,reorder,deadcode,reduce,garbageCollector,dataflow,history,multiplex

so there are many optimizer,but why when i debug MonetDB,and dump the mal of my sql statement,but i can't find the optimizer mal ,and don't enter the optimizer? like there are no optimizer,

if you prefix your SQL query with EXPLAIN to see the MAL plan, you get the optimizer MAL plan, i.e., all optimizers have already been called and done their work. Stefan

...

2010/8/11 Stefan Manegold

...
Yes, if you write MAL "by hand" (or have some program create it) that does explicitly call a MAL optimizer, that MAL optimizer is indeed used to optimize the MAL code according to its very purpose.

Stefan

On Wed, Aug 11, 2010 at 03:49:47PM +0800, kun ren wrote:

...
It is only used by SQL? and how to designation the optimiser？but when I write MAL,for example, i:=0; b:= "done"; barrier go:= true; c:=i+1; d:="step"; v:=d; io.print(v); i:=c; redo go:= i<2; exit go; io.print(b); optimizer.aliasRemoval();

the last optimizer.aliasRemoval() is used for optimizing?

2010/8/11 Fabian Groffen

...
...
Recently,I am intersting in MAL optimize，and have read the manual of

On 11-08-2010 15:25:15 +0800, kun ren wrote: the

...
MAL optimize, but it is so long, Possible if we want to use mal optimize ,we must degignation the optimize consideration, such as alias removal, constant expression,join path optimizer;And then I dedug the MonetDB,but default it don't use any optimize.so what do you think about the mal optimize?

It is only used when you use SQL. The sql_optimizer setting in monetdb5.conf controls which optimisers are run, which by default are quite a few.

...
...
This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

...
------------------------------------------------------------------------------

...
This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev

...
_______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

kun ren

8:38 a.m.

Thanks，professor Stefan Manegold,when I use explain,I get the optimizer MAL plan. I have another question, so we know that many classic optimizer for row-oriented database，and can I say the MAL optimizer is unique for column-oriented database such as MonetDB? or some of MAL optimizer is unique for column-oriented? Best regards! 2010/8/11 Stefan Manegold

...

On Wed, Aug 11, 2010 at 04:23:42PM +0800, kun ren wrote:

...
I read sql_optimizer setting in monetdb5.conf ,and default setting is: sql_optimizer=default_pipe

default_pipe=inline,remap,evaluate,costModel,coercions,emptySet,aliases,mitosis,mergetable,deadcode,commonTerms,joinPath,reorder,deadcode,reduce,garbageCollector,dataflow,history,multiplex

...
so there are many optimizer,but why when i debug MonetDB,and dump the mal

...
my sql statement,but i can't find the optimizer mal ,and don't enter

of the

...
optimizer? like there are no optimizer,

if you prefix your SQL query with EXPLAIN to see the MAL plan, you get the optimizer MAL plan, i.e., all optimizers have already been called and done their work.

Stefan

...
2010/8/11 Stefan Manegold

...
Yes, if you write MAL "by hand" (or have some program create it) that

does

...
...
explicitly call a MAL optimizer, that MAL optimizer is indeed used to optimize the MAL code according to its very purpose.

Stefan

On Wed, Aug 11, 2010 at 03:49:47PM +0800, kun ren wrote:

...
It is only used by SQL? and how to designation the optimiser？but when I write MAL,for example, i:=0; b:= "done"; barrier go:= true; c:=i+1; d:="step"; v:=d; io.print(v); i:=c; redo go:= i<2; exit go; io.print(b); optimizer.aliasRemoval();

the last optimizer.aliasRemoval() is used for optimizing?

2010/8/11 Fabian Groffen

...
...
Recently,I am intersting in MAL optimize，and have read the manual of

On 11-08-2010 15:25:15 +0800, kun ren wrote: the

...
MAL optimize, but it is so long, Possible if we want to use mal optimize ,we must degignation the optimize consideration, such as alias removal, constant expression,join path optimizer;And then I dedug the MonetDB,but default it don't use any optimize.so what do you think about the mal optimize?

It is only used when you use SQL. The sql_optimizer setting in monetdb5.conf controls which optimisers are run, which by default are quite a few.

...
...
...
...
This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

...

...
...
...
This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev

...
_______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

Stefan Manegold

9:04 a.m.

The ideas / intension of some MAL optimizers, such as alias removal, dead code elimination, (to some extend) join ordering, etc. are generic and traditional, both in database query optimization and progarmming language / compiler optimization. The genral optimizer design and architecture combining (to some extend) both database query optimization and progarmming language / compiler optimization, as well as some of the optimizers (e.g., mitosis, mergtable, dataflow, etc.), and obviously the very implementation of all MAL optimizers, is very unique to MonetDB5/SQL and MAL. Stefan On Wed, Aug 11, 2010 at 04:38:01PM +0800, kun ren wrote:

...

Thanks，professor Stefan Manegold,when I use explain,I get the optimizer MAL plan. I have another question, so we know that many classic optimizer for row-oriented database，and can I say the MAL optimizer is unique for column-oriented database such as MonetDB? or some of MAL optimizer is unique for column-oriented? Best regards!

2010/8/11 Stefan Manegold

...
On Wed, Aug 11, 2010 at 04:23:42PM +0800, kun ren wrote:

...
I read sql_optimizer setting in monetdb5.conf ,and default setting is: sql_optimizer=default_pipe

default_pipe=inline,remap,evaluate,costModel,coercions,emptySet,aliases,mitosis,mergetable,deadcode,commonTerms,joinPath,reorder,deadcode,reduce,garbageCollector,dataflow,history,multiplex

...
so there are many optimizer,but why when i debug MonetDB,and dump the mal

...
my sql statement,but i can't find the optimizer mal ,and don't enter

of the

...
optimizer? like there are no optimizer,

if you prefix your SQL query with EXPLAIN to see the MAL plan, you get the optimizer MAL plan, i.e., all optimizers have already been called and done their work.

Stefan

...
2010/8/11 Stefan Manegold

...
Yes, if you write MAL "by hand" (or have some program create it) that

does

...
...
explicitly call a MAL optimizer, that MAL optimizer is indeed used to optimize the MAL code according to its very purpose.

Stefan

On Wed, Aug 11, 2010 at 03:49:47PM +0800, kun ren wrote:

...
It is only used by SQL? and how to designation the optimiser？but when I write MAL,for example, i:=0; b:= "done"; barrier go:= true; c:=i+1; d:="step"; v:=d; io.print(v); i:=c; redo go:= i<2; exit go; io.print(b); optimizer.aliasRemoval();

the last optimizer.aliasRemoval() is used for optimizing?

2010/8/11 Fabian Groffen

...
On 11-08-2010 15:25:15 +0800, kun ren wrote: > Recently,I am intersting in MAL optimize，and have read the manual of the > MAL optimize, but it is so long, Possible if we want to use mal optimize ,we > must degignation the optimize consideration, such as alias removal, > constant expression,join path optimizer;And then I dedug the MonetDB,but > default it don't use any optimize.so what do you think about the mal > optimize?

It is only used when you use SQL. The sql_optimizer setting in monetdb5.conf controls which optimisers are run, which by default are quite a few.

...
...
...
...
This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

...

...
...
...
This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev

...
_______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

kun ren

9:21 a.m.

Thanks very much, you means the ideas and intension of MAL optimizers contain three parts: 1. programming language/compiler optimization 2. databose query optimization 3. some optimization only for column-oriented database but not for row-oriented database,such as mitosis,mergtable,dataflow etc Best regards! 2010/8/11 Stefan Manegold

...

The ideas / intension of some MAL optimizers, such as alias removal, dead code elimination, (to some extend) join ordering, etc. are generic and traditional, both in database query optimization and progarmming language / compiler optimization. The genral optimizer design and architecture combining (to some extend) both database query optimization and progarmming language / compiler optimization, as well as some of the optimizers (e.g., mitosis, mergtable, dataflow, etc.), and obviously the very implementation of all MAL optimizers, is very unique to MonetDB5/SQL and MAL.

Stefan

...
Thanks，professor Stefan Manegold,when I use explain,I get the optimizer MAL plan. I have another question, so we know that many classic optimizer for row-oriented database，and can I say the MAL optimizer is unique for column-oriented database such as MonetDB? or some of MAL optimizer is unique for column-oriented? Best regards!

2010/8/11 Stefan Manegold

...
On Wed, Aug 11, 2010 at 04:23:42PM +0800, kun ren wrote:

...
I read sql_optimizer setting in monetdb5.conf ,and default setting is: sql_optimizer=default_pipe

default_pipe=inline,remap,evaluate,costModel,coercions,emptySet,aliases,mitosis,mergetable,deadcode,commonTerms,joinPath,reorder,deadcode,reduce,garbageCollector,dataflow,history,multiplex

...
...
so there are many optimizer,but why when i debug MonetDB,and dump the

...
my sql statement,but i can't find the optimizer mal ,and don't enter

mal of the

...
optimizer? like there are no optimizer,

if you prefix your SQL query with EXPLAIN to see the MAL plan, you get

...
...
optimizer MAL plan, i.e., all optimizers have already been called and done their work.

Stefan

...
2010/8/11 Stefan Manegold

...
Yes, if you write MAL "by hand" (or have some program create it)

...
...
does

...
...
explicitly call a MAL optimizer, that MAL optimizer is indeed used to optimize the MAL code according to its very purpose.

Stefan

On Wed, Aug 11, 2010 at 03:49:47PM +0800, kun ren wrote:

...
It is only used by SQL? and how to designation the optimiser？but when I write MAL,for example, i:=0; b:= "done"; barrier go:= true; c:=i+1; d:="step"; v:=d; io.print(v); i:=c; redo go:= i<2; exit go; io.print(b); optimizer.aliasRemoval();

the last optimizer.aliasRemoval() is used for optimizing?

2010/8/11 Fabian Groffen

> On 11-08-2010 15:25:15 +0800, kun ren wrote: > > Recently,I am intersting in MAL optimize，and have read the manual of > the > > MAL optimize, but it is so long, Possible if we want to use mal optimize > ,we > > must degignation the optimize consideration, such as alias removal, > > constant expression,join path optimizer;And then I dedug the MonetDB,but > > default it don't use any optimize.so what do you think about

On Wed, Aug 11, 2010 at 04:38:01PM +0800, kun ren wrote: the that the

...
...
mal

...
...
...
> > optimize? > > It is only used when you use SQL. The sql_optimizer setting in > monetdb5.conf controls which optimisers are run, which by default are > quite a few. > > >

...
...
...
...
...
> This SF.net email is sponsored by > > Make an app they can't live without > Enter the BlackBerry Developer Challenge > http://p.sf.net/sfu/RIM-dev2dev > _______________________________________________ > Monetdb-developers mailing list > Monetdb-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/monetdb-developers >

...

...
...
...
...
...
This SF.net email is sponsored by

Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev

...
_______________________________________________ Monetdb-developers mailing list Monetdb-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-developers

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

kun ren

9:29 a.m.

what I think is right? the ideas and intension of MAL optimizers contain three parts: 1. programming language/compiler optimization 2. databose query optimization 3. some optimization only for column-oriented database but not for row-oriented database,such as mitosis,mergtable,dataflow etc.as a whole, all MAL optimizers is unque for MonetDB. Do I understand right? 在 2010年8月11日下午5:21，kun ren 写道：

...

Thanks very much, you means the ideas and intension of MAL optimizers contain three parts: 1. programming language/compiler optimization 2. databose query optimization 3. some optimization only for column-oriented database but not for row-oriented database,such as mitosis,mergtable,dataflow etc Best regards!

2010/8/11 Stefan Manegold

...
The ideas / intension of some MAL optimizers, such as alias removal, dead code elimination, (to some extend) join ordering, etc. are generic and traditional, both in database query optimization and progarmming language / compiler optimization. The genral optimizer design and architecture combining (to some extend) both database query optimization and progarmming language / compiler optimization, as well as some of the optimizers (e.g., mitosis, mergtable, dataflow, etc.), and obviously the very implementation of all MAL optimizers, is very unique to MonetDB5/SQL and MAL.

Stefan

...
Thanks，professor Stefan Manegold,when I use explain,I get the optimizer MAL plan. I have another question, so we know that many classic optimizer for row-oriented database，and can I say the MAL optimizer is unique for column-oriented database such as MonetDB? or some of MAL optimizer is unique for column-oriented? Best regards!

2010/8/11 Stefan Manegold

...
On Wed, Aug 11, 2010 at 04:23:42PM +0800, kun ren wrote:

...
I read sql_optimizer setting in monetdb5.conf ,and default setting is: sql_optimizer=default_pipe

default_pipe=inline,remap,evaluate,costModel,coercions,emptySet,aliases,mitosis,mergetable,deadcode,commonTerms,joinPath,reorder,deadcode,reduce,garbageCollector,dataflow,history,multiplex

...
...
so there are many optimizer,but why when i debug MonetDB,and dump

...
...
...
my sql statement,but i can't find the optimizer mal ,and don't enter

of the

...
optimizer? like there are no optimizer,

if you prefix your SQL query with EXPLAIN to see the MAL plan, you get

...
...
optimizer MAL plan, i.e., all optimizers have already been called and done their work.

Stefan

...
2010/8/11 Stefan Manegold

...
Yes, if you write MAL "by hand" (or have some program create it)

...
...
does

...
...
explicitly call a MAL optimizer, that MAL optimizer is indeed used to optimize the MAL code according to its very purpose.

Stefan

On Wed, Aug 11, 2010 at 03:49:47PM +0800, kun ren wrote: > It is only used by SQL? and how to designation the optimiser？but when I > write MAL,for example, > i:=0; > b:= "done"; > barrier go:= true; > c:=i+1; > d:="step"; > v:=d; > io.print(v); > i:=c; > redo go:= i<2; > exit go; > io.print(b); > optimizer.aliasRemoval(); > > the last optimizer.aliasRemoval() is used for optimizing? > > 2010/8/11 Fabian Groffen > > > On 11-08-2010 15:25:15 +0800, kun ren wrote: > > > Recently,I am intersting in MAL optimize，and have read

...
...
manual

...
...
of > > the > > > MAL optimize, but it is so long, Possible if we want to use mal optimize > > ,we > > > must degignation the optimize consideration, such as alias removal, > > > constant expression,join path optimizer;And then I dedug the MonetDB,but > > > default it don't use any optimize.so what do you think about

On Wed, Aug 11, 2010 at 04:38:01PM +0800, kun ren wrote: the mal the that the the

...
...
mal

...
...
> > > optimize? > > > > It is only used when you use SQL. The sql_optimizer setting in > > monetdb5.conf controls which optimisers are run, which by default are > > quite a few. > > > > > >

...
...
...
...
> > This SF.net email is sponsored by > > > > Make an app they can't live without > > Enter the BlackBerry Developer Challenge > > http://p.sf.net/sfu/RIM-dev2dev > > _______________________________________________ > > Monetdb-developers mailing list > > Monetdb-developers@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/monetdb-developers > >

>

...
...
...
...
> This SF.net email is sponsored by > > Make an app they can't live without > Enter the BlackBerry Developer Challenge > http://p.sf.net/sfu/RIM-dev2dev

> _______________________________________________ > Monetdb-developers mailing list > Monetdb-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/monetdb-developers

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

-- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |

5252

Age (days ago)

5252

Last active (days ago)

List overview

Download

9 comments

3 participants

participants (3)

Fabian Groffen
kun ren
Stefan Manegold