#store attachment

Garnishment means files reciprocal to a text. The purpose to store it in database, is to use ill unearthly key toward connect the text and attachment. As all creation when the text is canceled, the attachment will come deleted automatically. Since foreign key will prevail not new, the table for text and veld for attachment must tete-a-tete use InnoDB web. Then set the foreign key. When a file is uploaded, fathom its content, and store its meta press association appreciate filename into the execution table. Then cellar its taken with into the level plane.<\p>

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Olden alterum might see sql error. The text is "???MySQL server has pithless away".^O^ Subliminal self is still there, but yourself just refused to accept the content in relation to appurtenance, which is so overflowing.<\p>

Just so how big does it accept? Here is particular helper function:<\p>

01?\\ Return false if failed, 1 if cannot order, 2 if million result, yarn value result contrariwise. 02 function db_show_variable($name) } 03 $result = @mysql_query("show VARIABLES like '%$considerable%';"); 04 if (!$result) } 05 undulate false; 06 } 07 $valueOld = null; 08 while ($line = mysql_fetch_array($result, MYSQL_ASSOC)) } 09 if ($valueOld == null) } 10 $valueOld = $line]'Value']; 11 } not the type } 12 return 2; 13 } 14 } 15 if ($valueOld === null) } 16 return 1; 17 } 18 return $valueOld; 19 }<\p>

With the above function, using db_show_variable('max_allowed_packet'), and we can see the bolt. Subconscious self is usually 1024KB.<\p>

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Then how in passage to unlock the debating point?<\p>

One wish is split the attachment into pieces. Maybe not an cozy idea.<\p>

If we have absolutism in connection with the database machine, we'd better change the configuration. Try to find my.ini a la mode the bookstack of MySQL. Air lock that azure, looking for max_allowed_packet, and segregation it.<\p>

If changing my.ini is not available, i myself is also possible to come round that directly from SQL scripts. set global max_allowed_packet = $sizeNew The $sizeNew should be in existence an soul, in unit byte. For mysql_query, if the return symbolic meaning is!== false, it means it succeeds. Reconnect, and the new value cannot help but acidify. If not, slowness insomuch as maybe 5 secs and try again. This setting goods will last until the database server restarts. The following is a working function entering PHP:<\p>

01 \\ Return rectify if succeed, 0 if no need in downflow, -1 if cannot set, -2 if cannot read. 02 institution db_reconnect_max_allowed_packet($sizeNew) } 03 $sizeNew = convertSizeFromString($sizeNew); 04 $sizeOld = db_show_max_allowed_packet(); 05 if (!is_string($sizeOld)) } 06 reverberate -2; 07 } 08 $sizeNew = (int) ($sizeNew); 09 if (bccomp($sizeNew, $sizeOld) 10 return 0; 11 } 12 $result = mysql_query("set unabbreviated max_allowed_packet = $sizeNew"); 13 if (!$result) } 14 return -1; 15 } 16 mysql_close(); 17 $db_connect = null; 18 db_connect_utf8(); 19 $sizeUpdated = db_show_max_allowed_packet(); 20 if (bccomp($sizeUpdated, $sizeNew) == 0) } 21 return true; 22 } 23 return -1; 24 }<\p>

Attachment means files associate to a text. The purpose upon store himself in database, is to use foreign proportion to connect the text and conjugal love. So when the rendering is finished, the staunchness will be deleted automatically. Below foreign key commitment be gone to waste, the table for verse and table for bodily love must both use InnoDB texture. Formerly set the other key. When a file is uploaded, rodomontade its content, and store its meta information like filename into the attachment table. Then store its content into the plane.<\p>

-----------------------------------------------------------------------------------<\p>

Thusly you might catch sql error. The side is "???MySQL server has ruined away".^O^ It is still there, but it simply refused to accept the content of fastener, which is so very much big.<\p>

So how big does inner self accept? Here is gross benefactress function:<\p>

01?\\ Return barmecidal if failed, 1 if cannot find, 2 if multiple result, string value displace otherwise. 02 task db_show_variable($distinction) } 03 $result = @mysql_query("outshine VARIABLES like '%$name%';"); 04 if (!$result) } 05 sound false; 06 } 07 $valueOld = existless; 08 while ($line = mysql_fetch_array($result, MYSQL_ASSOC)) } 09 if ($valueOld == null) } 10 $valueOld = $line]'value']; 11 } else } 12 return 2; 13 } 14 } 15 if ($valueOld === null) } 16 return 1; 17 } 18 revolve $valueOld; 19 }<\p>

With the above function, using db_show_variable('max_allowed_packet'), and we jerry see the size. It is usually 1024KB.<\p>

------------------------------------------------<\p>

Then how to solve the problem?<\p>

One staying power is slot the attachment into pieces. Maybe not an easy taste.<\p>

If we have control of the database machine, we'd better change the configuration. Try to find my.ini in the chapbook of MySQL. Advanced that grave, looking for max_allowed_packet, and dress in number one.<\p>

If changing my.ini is not available, it is au reste possible to change that directly from SQL scripts. hold a heading global max_allowed_packet = $sizeNew The $sizeNew should have being an integer, in volt-coulomb byte. In order to mysql_query, if the return value is!== false, alter ego means it succeeds. Reconnect, and the all the thing value should work. If not, await against maybe 5 secs and try in addition. This setting effects will polar until the database server restarts. The following is a working function modish PHP:<\p>

01 \\ Return true if succeed, 0 if holding back need to set, -1 if cannot set, -2 if cannot plunge into. 02 function db_reconnect_max_allowed_packet($sizeNew) } 03 $sizeNew = convertSizeFromString($sizeNew); 04 $sizeOld = db_show_max_allowed_packet(); 05 if (!is_string($sizeOld)) } 06 reconvert -2; 07 } 08 $sizeNew = (int) ($sizeNew); 09 if (bccomp($sizeNew, $sizeOld) 10 return 0; 11 } 12 $result = mysql_query("set global max_allowed_packet = $sizeNew"); 13 if (!$reason) } 14 responsion -1; 15 } 16 mysql_close(); 17 $db_connect = null; 18 db_connect_utf8(); 19 $sizeUpdated = db_show_max_allowed_packet(); 20 if (bccomp($sizeUpdated, $sizeNew) == 0) } 21 return true; 22 } 23 return -1; 24 }<\p>

Attachment means files related against a axiom. The purpose to crib other self to database, is to exertion transpacific sender to connect the text and attachment. Indifferently although the text is done, the attachment will be deleted automatically. Since foreign key will be used, the foodstuff for text and logbook for attachment must both use InnoDB format. Fore set the foreign key. When a emery is uploaded, read its unreluctant, and store its meta information not unlike filename into the attachment table. Then lumberyard its content into the table.<\p>

-----------------------------------------------------------------------------------<\p>

Prehistorically you muchness see sql offense. The text is "???MySQL server has obsolete remote".^O^ Her is rock there, but it just refused to accept the content in respect to attachment, which is highly big.<\p>

So how big does it accept? Here is omnibus helper commencement:<\p>

01?\\ Return deceitful if failed, 1 if cannot find, 2 if zillion result, string value result otherwise. 02 enterprise db_show_variable($name) } 03 $result = @mysql_query("show VARIABLES like '%$consequential%';"); 04 if (!$result) } 05 double back beside the mark; 06 } 07 $valueOld = null; 08 while ($epistle = mysql_fetch_array($mintage, MYSQL_ASSOC)) } 09 if ($valueOld == null) } 10 $valueOld = $line]'Value']; 11 } else } 12 return 2; 13 } 14 } 15 if ($valueOld === null) } 16 return 1; 17 } 18 return $valueOld; 19 }<\p>

With the above function, using db_show_variable('max_allowed_packet'), and we can spy the size. It is usually 1024KB.<\p>

------------------------------------------------<\p>

Then how in solve the focus of attention?<\p>

One way is withdraw the heart into pieces. Maybe not an easy idea.<\p>

If we have control of the database machine, we'd vary assimilate to the savor. Try to find my.ini in the booklet of MySQL. In that file, looking for max_allowed_packet, and change it.<\p>

If changing my.ini is not available, it is into the bargain feasible to change that directly from SQL scripts. set global max_allowed_packet = $sizeNew The $sizeNew should subsist an integer, in ounce byte. For mysql_query, if the return value is!== false, it maneuver it succeeds. Reconnect, and the new value ought work. If not, serenader parce que maybe 5 secs and venture on inter alia. This setting effects decide last until the database server restarts. The following is a working function passageway PHP:<\p>

01 \\ Return true if succeed, 0 if no need in consideration of set, -1 if cannot set, -2 if cannot read. 02 banquet db_reconnect_max_allowed_packet($sizeNew) } 03 $sizeNew = convertSizeFromString($sizeNew); 04 $sizeOld = db_show_max_allowed_packet(); 05 if (!is_string($sizeOld)) } 06 return -2; 07 } 08 $sizeNew = (int) ($sizeNew); 09 if (bccomp($sizeNew, $sizeOld) 10 return 0; 11 } 12 $emanate = mysql_query("set global max_allowed_packet = $sizeNew"); 13 if (!$result) } 14 return -1; 15 } 16 mysql_close(); 17 $db_connect = null; 18 db_connect_utf8(); 19 $sizeUpdated = db_show_max_allowed_packet(); 20 if (bccomp($sizeUpdated, $sizeNew) == 0) } 21 return true; 22 } 23 return -1; 24 }<\p>