How to ignore certain MySQL tables when importing a database?

Question

I have a large SQL file with one database and about 150 tables. I would like to use mysqlimport to import that database, however, I would like the import process to ignore or skip over a couple of tables. What is the proper syntax to import all tables, but ignore some of them? Thank you.

Answer 1

The accepted answer by RandomSeed could take a long time! Importing the table (just to drop it later) could be very wasteful depending on size.

For a file created using

mysqldump -u user -ppasswd --opt --routines DBname > DBdump.sql

I currently get a file about 7GB, 6GB of which is data for a log table that I don't 'need' to be there; reloading this file takes a couple of hours. If I need to reload (for development purposes, or if ever required for a live recovery) I skim the file thus:

sed '/INSERT INTO `TABLE_TO_SKIP`/d' DBdump.sql > reduced.sql

And reload with:

mysql -u user -ppasswd DBname < reduced.sql

This gives me a complete database, with the "unwanted" table created but empty. If you really don't want the tables at all, simply drop the empty tables after the load finishes.

For multiple tables you could do something like this:

sed '/INSERT INTO `TABLE1_TO_SKIP`/d' DBdump.sql | \
sed '/INSERT INTO `TABLE2_TO_SKIP`/d' | \
sed '/INSERT INTO `TABLE3_TO_SKIP`/d' > reduced.sql

There IS a 'gotcha' - watch out for procedures in your dump that might contain "INSERT INTO TABLE_TO_SKIP".

Answer 2

For anyone working with .sql.gz files; I found the following solution to be very useful. Our database was 25GB+ and I had to remove the log tables.

gzip -cd "./mydb.sql.gz" | sed -r '/INSERT INTO `(log_table_1|log_table_2|log_table_3|log_table_4)`/d' | gzip > "./mydb2.sql.gz"

Thanks to the answer of Don and comment of Xosofox and this related post: Use zcat and sed or awk to edit compressed .gz text file

Answer 3

mysqlimport is not the right tool for importing SQL statements. This tool is meant to import formatted text files such as CSV. What you want to do is feed your sql dump directly to the mysql client with a command like this one:

bash > mysql -D your_database < your_sql_dump.sql

Neither mysql nor mysqlimport provide the feature you need. Your best chance would be importing the whole dump, then dropping the tables you do not want.

If you have access to the server where the dump comes from, then you could create a new dump with mysqldump --ignore-table=database.table_you_dont_want1 --ignore-table=database.table_you_dont_want2 ....

---

Check out this answer for a workaround to skip importing some table

Answer 4

Little old, but figure it might still come in handy...

I liked @Don's answer (https://stackoverflow.com/a/26379517/1446005) but found it very annoying that you'd have to write to another file first...
In my particular case this would take too much time and disc space

So I wrote a little bash script:

#!/bin/bash

tables=(table1_to_skip table2_to_skip ... tableN_to_skip)


tableString=$(printf "|%s" "${tables[@]}")
trimmed=${tableString:1}
grepExp="INSERT INTO \`($trimmed)\`"

zcat $1 | grep -vE "$grepExp" | mysql -uroot -p

this does not generate a new sql script but pipes it directly to the database
also, it does create the tables, just doesn't import the data (which was the problem I had with huge log tables)

Answer 5

Unless you have ignored the tables during the dump with mysqldump --ignore-table=database.unwanted_table, you have to use some script or tool to filter out the data you don't want to import from the dump file before passing it to mysql client.

Here is a bash/sh function that would exclude the unwanted tables from a SQL dump on the fly (through pipe):

# Accepts one argument, the list of tables to exclude (case-insensitive).
# Eg. filt_exclude '%session% action_log %_cache'
filt_exclude() {
    local excl_tns;
    if [ -n "$1" ]; then
        # trim & replace /[,;\s]+/ with '|' & replace '%' with '[^`]*'
        excl_tns=$(echo "$1" | sed -r 's/^[[:space:]]*//g; s/[[:space:]]*$//g; s/[[:space:]]+/|/g; s/[,;]+/|/g; s/%/[^\`]\*/g');

        grep -viE "(^INSERT INTO \`($excl_tns)\`)|(^DROP TABLE (IF EXISTS )?\`($excl_tns)\`)|^LOCK TABLES \`($excl_tns)\` WRITE" | \
        sed 's/^CREATE TABLE `/CREATE TABLE IF NOT EXISTS `/g'        
    else
        cat
    fi
}

Suppose you have a dump created like so:

MYSQL_PWD="my-pass" mysqldump -u user --hex-blob db_name | \
pigz -9 > dump.sql.gz

And want to exclude some unwanted tables before importing:

pigz -dckq dump.sql.gz | \
filt_exclude '%session% action_log %_cache' | \
MYSQL_PWD="my-pass" mysql -u user db_name

Or you could pipe into a file or any other tool before importing to DB.

Answer 6

If desired, you can do this one table at a time:

mysqldump -p sourceDatabase tableName > tableName.sql
mysql -p -D targetDatabase < tableName.sql

Answer 7

Here is my script to exclude some tables from mysql dump I use it to restore DB when need to keep orders and payments data

exclude_tables_from_dump.sh

#!/bin/bash

if [ ! -f "$1" ];
then
    echo "Usage: $0 mysql_dump.sql"
    exit
fi

declare -a TABLES=(
user
order
order_product
order_status
payments
)

CMD="cat $1"
for TBL in "${TABLES[@]}";do
    CMD+="|sed 's/DROP TABLE IF EXISTS \`${TBL}\`/# DROP TABLE IF EXIST \`${TBL}\`/g'"
    CMD+="|sed 's/CREATE TABLE \`${TBL}\`/CREATE TABLE IF NOT EXISTS \`${TBL}\`/g'"
    CMD+="|sed -r '/INSERT INTO \`${TBL}\`/d'"
    CMD+="|sed '/DELIMITER\ \;\;/,/DELIMITER\ \;/d'"
done

eval $CMD

It avoid DROP and reCREATE of tables and inserting data to this tables. Also it strip all FUNCTIONS and PROCEDURES that stored between DELIMITER ;; and DELIMITER ;

Answer 8

I would not use it on production but if I would have to import some backup quickly that contains many smaller table and one big monster table that might take hours to import I would most probably "grep -v unwanted_table_name original.sql > reduced.sql

and then mysql -f < reduced.sql

Answer 9

Beside the great answers in this topic, It could be that your .sql file does not have the INSERTS with this for every line:

INSERT INTO `log`

But they are actually inserted like this:

LOCK TABLES `log` WRITE;

INSERT INTO `log` (`id`, `data`)
VALUES
  (1,'The log content'),
  (2,'The log content'),
  (3,'The log content'),
  (4,'The log content')
    
UNLOCK TABLES;

You'll want to exclude everything between LOCK TABLES `log` WRITE; and the next UNLOCK TABLES;

gzip -dc "$1" | sed \
-e '/LOCK TABLES `log` WRITE;/,/^UNLOCK TABLES/d;' \
-e '/LOCK TABLES `some_other_table` WRITE;/,/^UNLOCK TABLES/d;' \
| gzip > reduced_$(date '+%F_%T').sql.gz

Put that in a reduce_db.sh somewhere on your computer and every time you need it you execute it like this

bash /folder/to/reduce_db.sh /path/to/big_db_file.sql.gz

Good to know, only exclude data of which no other data in the database is dependent on. Otherwise your reduced database is inconsistent in the end.