How do I split the output from mysqldump into smaller files?

There is this excellent mysqldumpsplitter script which comes with tons of option for when it comes to extracting-from-mysqldump.

I would copy the recipe here to choose your case from:

1) Extract single database from mysqldump:

sh mysqldumpsplitter.sh --source filename --extract DB --match_str database-name

Above command will create sql for specified database from specified "filename" sql file and store it in compressed format to database-name.sql.gz.

2) Extract single table from mysqldump:

sh mysqldumpsplitter.sh --source filename --extract TABLE --match_str table-name

Above command will create sql for specified table from specified "filename" mysqldump file and store it in compressed format to database-name.sql.gz.

3) Extract tables matching regular expression from mysqldump:

sh mysqldumpsplitter.sh --source filename --extract REGEXP --match_str regular-expression

Above command will create sqls for tables matching specified regular expression from specified "filename" mysqldump file and store it in compressed format to individual table-name.sql.gz.

4) Extract all databases from mysqldump:

sh mysqldumpsplitter.sh --source filename --extract ALLDBS

Above command will extract all databases from specified "filename" mysqldump file and store it in compressed format to individual database-name.sql.gz.

5) Extract all table from mysqldump:

sh mysqldumpsplitter.sh --source filename --extract ALLTABLES

Above command will extract all tables from specified "filename" mysqldump file and store it in compressed format to individual table-name.sql.gz.

6) Extract list of tables from mysqldump:

sh mysqldumpsplitter.sh --source filename --extract REGEXP --match_str '(table1|table2|table3)'

Above command will extract tables from the specified "filename" mysqldump file and store them in compressed format to individual table-name.sql.gz.

7) Extract a database from compressed mysqldump:

sh mysqldumpsplitter.sh --source filename.sql.gz --extract DB --match_str 'dbname' --decompression gzip

Above command will decompress filename.sql.gz using gzip, extract database named "dbname" from "filename.sql.gz" & store it as out/dbname.sql.gz

8) Extract a database from compressed mysqldump in an uncompressed format:

sh mysqldumpsplitter.sh --source filename.sql.gz --extract DB --match_str 'dbname' --decompression gzip --compression none

Above command will decompress filename.sql.gz using gzip and extract database named "dbname" from "filename.sql.gz" & store it as plain sql out/dbname.sql

9) Extract alltables from mysqldump in different folder:

sh mysqldumpsplitter.sh --source filename --extract ALLTABLES --output_dir /path/to/extracts/

Above command will extract all tables from specified "filename" mysqldump file and extracts tables in compressed format to individual files, table-name.sql.gz stored under /path/to/extracts/. The script will create the folder /path/to/extracts/ if not exists.

10) Extract one or more tables from one database in a full-dump:

Consider you have a full dump with multiple databases and you want to extract few tables from one database.

Extract single database: sh mysqldumpsplitter.sh --source filename --extract DB --match_str DBNAME --compression none

Extract all tables sh mysqldumpsplitter.sh --source out/DBNAME.sql --extract REGEXP --match_str "(tbl1|tbl2)" though we can use another option to do this in single command as follows:

sh mysqldumpsplitter.sh --source filename --extract DBTABLE --match_str "DBNAME.(tbl1|tbl2)" --compression none

Above command will extract both tbl1 and tbl2 from DBNAME database in sql format under folder "out" in current directory.

You can extract single table as follows:

sh mysqldumpsplitter.sh --source filename --extract DBTABLE --match_str "DBNAME.(tbl1)" --compression none

11) Extract all tables from specific database:

mysqldumpsplitter.sh --source filename --extract DBTABLE --match_str "DBNAME.*" --compression none

Above command will extract all tables from DBNAME database in sql format and store it under "out" directory.

12) List content of the mysqldump file

mysqldumpsplitter.sh --source filename --desc

Above command will list databases and tables from the dump file.

You may later choose to load the files: zcat filename.sql.gz | mysql -uUSER -p -hHOSTNAME

  • Also once you extract single table which you think is still bigger, you can use linux split command with number of lines to further split the dump. split -l 10000 filename.sql

  • That said, if that is your need (coming more often), you might consider using mydumper which actually creates individual dumps you wont need to split!


This bash script splits a dumpfile of one database into separate files for each table and names with csplit and names them accordingly:

#!/bin/bash

####
# Split MySQL dump SQL file into one file per table
# based on https://gist.github.com/jasny/1608062
####

#adjust this to your case:
START="/-- Table structure for table/"
# or 
#START="/DROP TABLE IF EXISTS/"


if [ $# -lt 1 ] || [[ $1 == "--help" ]] || [[ $1 == "-h" ]] ; then
        echo "USAGE: extract all tables:"
        echo " $0 DUMP_FILE"
        echo "extract one table:"
        echo " $0 DUMP_FILE [TABLE]"
        exit
fi

if [ $# -ge 2 ] ; then
        #extract one table $2
        csplit -s -ftable $1 "/-- Table structure for table/" "%-- Table structure for table \`$2\`%" "/-- Table structure for table/" "%40103 SET TIME_ZONE=@OLD_TIME_ZONE%1"
else
        #extract all tables
        csplit -s -ftable $1 "$START" {*}
fi
 
[ $? -eq 0 ] || exit
 
mv table00 head
 
FILE=`ls -1 table* | tail -n 1`
if [ $# -ge 2 ] ; then
        # cut off all other tables
        mv $FILE foot
else
        # cut off the end of each file
        csplit -b '%d' -s -f$FILE $FILE "/40103 SET TIME_ZONE=@OLD_TIME_ZONE/" {*}
        mv ${FILE}1 foot
fi
 
for FILE in `ls -1 table*`; do
        NAME=`head -n1 $FILE | cut -d$'\x60' -f2`
        cat head $FILE foot > "$NAME.sql"
done
 
rm head foot table*

based on https://gist.github.com/jasny/1608062
and https://stackoverflow.com/a/16840625/1069083


First dump the schema (it surely fits in 2Mb, no?)

mysqldump -d --all-databases

and restore it.

Afterwards dump only the data in separate insert statements, so you can split the files and restore them without having to concatenate them on the remote server

mysqldump --all-databases --extended-insert=FALSE --no-create-info=TRUE

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Mysql

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