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SPAWK Tutorial

In this page we setup a MySQL/MariaDB test database and use SPAWK to access this database with AWK. You can download most of the files and scripts found in this page and run everything locally, though you must be careful in order not to damage your databases or other files or scripts. Have fun!

Download and install SPAWK

In order to run this tutorial, SPAWK must be downloaded and installed locally. After downloading SPAWK tarball, you may have to download the MySQL/MariaDB libmysqlclient.so dynamic library and mysql_config utility program in order to compile and link the spawk gawk dynamic extension. Refer to the [ Download ] page for further instructions on how to download and install SPAWK to your local system.

Warning!
Do not remove the spawk directory structure extracted from the SPAWK tarball after installation, because some files will be needed for this tutorial course to complete. After fininsihing this tutorial course the files will no longer be needed, so you can safely remove the whole spawk directory structure.

The chat application

This tutorial page is about a hypothetical chat application, where users all over the world can register and start chatting to each other. Users can setup relationships to other users marking them as friends or blocking them out. Users can also send off-line messages to each other, forming something like an internal email system inside the chat application. Later on we may add rooms, dates, or other useful objects to the chat application.

Our chat application consists of the usual major components such as web server, database, server side programs, client side programs etc. In this tutorial we cope mainly with the database and some server side SPAWK programming. We'll show you how to use SPAWK effectiveley for a wide range of database operations, from creating and populating the database, to producing useful database reports and statistics.

The chat database

The whole chat application lies on a MySQL/MariaDB database, holding users, user relations, messages etc. The schema of the database is by no means complicated; there exist less than five tables with a total of no more than twenty columns.

As expected, the most significant table in our chat database is a table holding the users of the application; we name this table as the user table. Users can be related to each other, that is they can mark selected users as friends, or block other users if they feel so. User relationships are kept, of course, in another table which we name as the relation table. Users may send offline messages to each other; sent messages form the message table. For now we don't need any other tables to setup our chat database.

The schema

We quote the chat database schema in SQL/DDL format:

-- Application "chat" is about web chatting between application users.
-- "chat" application, lies on the "chat" database were user data,
-- user relationships, user messages etc are stored.

-- (Re)create the "chat" database.

DROP DATABASE IF EXISTS `chat`
;

CREATE DATABASE `chat`
DEFAULT CHARSET = utf8mb4
DEFAULT COLLATE = utf8mb4_general_ci
;

-- Select "chat" database as the default database.

USE `chat`
;

-- Table "user" is the most significant table of the "chat" database.
-- Each row represents a registered user of the "chat" application.

CREATE TABLE `user` (
	`login`		VARCHAR(64) NOT NULL COMMENT 'Login name',
	`registration`	TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT 'Registration date',
	`name`		VARCHAR(128) NOT NULL COMMENT 'Full name',
	`email`		VARCHAR(128) NULL DEFAULT NULL COMMENT 'e-mail',
	`gender`	ENUM (
		'MALE',
		'FEMALE'
	) NULL DEFAULT NULL COMMENT 'Gender',
	`byear`		INTEGER(4) NULL DEFAULT NULL COMMENT 'Birth year',
	-- 		user passwords are stored in SHA1
	`password`	CHARACTER(40) COLLATE utf8_bin NOT NULL COMMENT 'Password',

	PRIMARY KEY (
		`login`
	) USING BTREE,

	INDEX (
		`name`
	) USING BTREE,

	UNIQUE INDEX (
		`email`
	) USING BTREE
)

ENGINE = InnoDB
COMMENT = 'Person table'
;

-- Table "relation" holds the relationships between users.
-- There are three kinds of relationships between any two users:
-- The users are unrelated, friends or blocked.

CREATE TABLE `relation` (
	`user`		VARCHAR(64) NOT NULL COMMENT 'Login name',
	`related`	VARCHAR(64) NOT NULL COMMENT 'Related login name',
	`relationship`	ENUM (
		'FRIEND',
		'BLOCKED'
	) NOT NULL COMMENT 'Relationship',

	PRIMARY KEY (
		`user`,
		`related`
	) USING BTREE,

	INDEX (
		`related`
	) USING BTREE
)

ENGINE = InnoDB
COMMENT = 'Relation table'
;

-- Table "message" holds the messages between users.

CREATE TABLE `message` (
	`id`		INTEGER(9) NOT NULL AUTO_INCREMENT COMMENT 'Message ID',
	`sender`	VARCHAR(64) NOT NULL COMMENT 'Sender',
	`recipient`	VARCHAR(64) NOT NULL COMMENT 'Recipient',
	`date`		TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT 'Date',
	`text`		VARCHAR(10000) NOT NULL COMMENT 'Text',

	PRIMARY KEY (
		`id`
	) USING BTREE,

	INDEX (
		`sender`
	) USING BTREE,

	INDEX (
		`recipient`
	) USING BTREE
)

ENGINE = InnoDB
COMMENT = 'Message table'
;

ALTER TABLE `relation` ADD FOREIGN KEY (
	`user`
) REFERENCES `user` (
	`login`
) ON UPDATE CASCADE ON DELETE CASCADE
;

ALTER TABLE `relation` ADD FOREIGN KEY (
	`related`
) REFERENCES `user` (
	`login`
) ON UPDATE CASCADE ON DELETE CASCADE
;

ALTER TABLE `message` ADD FOREIGN KEY (
	`sender`
) REFERENCES `user` (
	`login`
) ON UPDATE CASCADE ON DELETE CASCADE
;

ALTER TABLE `message` ADD FOREIGN KEY (
	`recipient`
) REFERENCES `user` (
	`login`
) ON UPDATE CASCADE ON DELETE CASCADE
;

-- Create user for generic DQL/DML access to "chat" database.

DROP USER IF EXISTS 'chat'@'localhost'
;

CREATE USER 'chat'@'localhost' IDENTIFIED BY 'xxx'
;

GRANT SELECT, INSERT, UPDATE, DELETE ON `chat`.* TO 'chat'@'localhost'
;

-- Create user for generic DQL access to "chatdql" database.

DROP USER IF EXISTS 'chatdql'@'localhost'
;

CREATE USER 'chatdql'@'localhost'
;

GRANT SELECT ON `chat`.* TO 'chatdql'@'localhost'
;

-- Create user for DDL/DQL/DML access to "chat" database.

DROP USER IF EXISTS 'chatadmin'@'localhost'
;

CREATE USER 'chatadmin'@'localhost' IDENTIFIED BY 'xxx'
;

GRANT ALL PRIVILEGES ON `chat`.* TO 'chatadmin'@'localhost'
;

Download

Creating the database

To create the database locally, you must download the file and run the following command as the root database user:

mysql -u root -p --force <schema.sql

However, there is no need to download the above file because this file is included in the spawk tarball downloaded earlier. The file schema.sql is located in the chat directory under the database directory.

Warning!!!
If you have an existing chat database in your system, it will be deleted!
Database users chat and chatadmin will be dropped too!

Populating the database

After creating the chat database and the chat and chatadmin database users, the application is ready to accept new user registrations. After registering at the application, users will start chatting, developing relationships and sending messages to each other and after a while we will have enough data in the chat database for testing and demonstrating SPAWK. However, we cannot wait for users to register in the chat application, moreover we have not setup any web server, neither we have developed any server or client side programs yet for the chat application to be up and running, so we decide to populate the database manually using existing data files.

In order to populate the chat database with test data, visit once again the spawk directory extracted from the downloaded SPAWK tarball. There exists a database directory, and a chat subdirectory under the database directory. In this directory there exist two data files namely the user.data containing 2000 test user data, and the relation.data containing 30000 relationship pairs between users. Our intention is to load these data files into the database by using SPAWK for the first time! In the same directory there exists an AWK script named populate.awk. Let's take a look:

@load "../../src/spawk/spawk"

BEGIN {
	FS = "\t"
	spawk_sesami["dbuser"] = "chat"
	spawk_sesami["dbpassword"] = "xxx"
	spawk_sesami["dbname"] = "chat"
}

NF == 7 {
	nf = 1
	login = $(nf++)
	registration = $(nf++)
	name = $(nf++)
	email = $(nf++)
	gender = $(nf++)
	byear = $(nf++)
	password = $(nf++)

	email = email ? spawk_escape(email) : "NULL"
	gender = gender ? spawk_escape(gender) : "NULL"
	byear = byear ? byear : "NULL"

	if (spawk_submit("INSERT INTO `user` (" \
		"`login`, " \
		"`registration`, " \
		"`name`, " \
		"`email`, " \
		"`gender`, " \
		"`byear`, " \
		"`password`" \
	") VALUES (" \
		spawk_escape(login) ", " \
		"FROM_UNIXTIME(" registration "), " \
		spawk_escape(name) ", " \
		email ", " \
		gender ", " \
		byear ", " \
		spawk_escape(password) \
	")") != 2)
	next

	if (!(++ucount % 1000))
	print ucount, "users inserted"

	next
}

NF == 3 {
	if (spawk_submit("INSERT INTO `relation` (" \
		"`user`, " \
		"`related`, " \
		"`relationship`" \
	") VALUES (" \
		spawk_escape($1) ", " \
		spawk_escape($2) ", " \
		spawk_escape($3) \
	")") != 2)
	next

	if (!(++rcount % 1000))
	print rcount, "relations inserted"

	next
}

{
	print $0 ": syntax error" >"/dev/stderr"
}

The test data files are the user.data file containing 2000 users and the relation.data file containing 30000 relationships. It's obvious that the relationships must be loaded after the users, because of the foreign key constraints between the corresponding tables. user.data file has 7 tab separated fields, while relation file has 3 tab separated fields: spawk_escape function takes a string argument and enclose this string in single quotes, after escaping single quotes found in the string, e.g. spawk_escape("panos") returns the string 'panos', while spawk_escape("smith's") returns the string 'smith\'s'.

The data files

File user.data:

fandrusyak0	1201744766	Freddie Andrusyak	fandrusyak0@usnews.com	MALE	1950	ce8b6645765ade3978743c7699314f5f40c4d9ac
mberns1	1386296786	Morton Berns	mberns1@hubpages.com	MALE	2010	7ad26d2cb2fff6105a027bf26f49d2829994836c
rgerard2	1452009325	Ricard Gerard	rgerard2@upenn.edu	MALE	1980	3d9431a625a1a468f67a4f06d51c890941c70046
aakerman3	1103639500	Al Akerman	aakerman3@goo.gl	MALE	1958	e36fcf09ca1d4cbdc3c0b30ca9bd211c12b6a96f
pgrimolbie4	1358742544	Pincus Grimolbie	pgrimolbie4@mayoclinic.com	MALE	1984	dc268bc27174b8f8619f1266e6fd259d7895a06e
mwarlaw5	1476605358	Manfred Warlaw	mwarlaw5@deviantart.com	MALE	1984	731bab1308a3c1e095e033390d8baf1ec8832fc2
abawdon6	1345679245	Alon Bawdon	abawdon6@msu.edu	MALE	1962	7814e192fd6b0a44a5d1503550a802742a89b2ae
bullyatt7	1114354347	Bevon Ullyatt	bullyatt7@joomla.org	MALE	1980	0a969515bbd302125105fa0946c3e4f062abf97e
aspridgen8	1121667581	Alaric Spridgen	aspridgen8@list-manage.com	MALE	1998	f2af7ca7654bf83e70f1af35937562c0caa3319a
vrayment9	1424094597	Vincenz Rayment	vrayment9@google.com.hk	MALE	1953	de68fbd1e262a988869c4b03015abc8a9d88f293
...

File relation.data:

mberns1	dinger59	BLOCKED
mberns1	cdackombe4f	FRIEND
mberns1	vgyenesfz	FRIEND
mberns1	mwillougheyii	FRIEND
mberns1	fcatterall5n	FRIEND
mberns1	tsiredio	FRIEND
mberns1	obountiffrm	FRIEND
mberns1	csamsinov	FRIEND
mberns1	ccraydenbo	BLOCKED
mberns1	mrugge6p	FRIEND
...

Before using SPAWK to load the data in the database, it's good to trace the populate.awk script one section at a time:

SPAWK setup

@load "spawk"

BEGIN {
	FS = "\t"
	spawk_sesami["dbuser"] = "chat"
	spawk_sesami["dbpassword"] = "xxx"
	spawk_sesami["dbname"] = "chat"
}
...

The very first line of the script is just the inclusion of the spawk dynamic extension. The extension has already been installed, possibly at the /usr/local/lib/gawk directory. This directory is searched by default from AWK, as AWKLIBPATH default value is "/usr/local/lib/gawk" as stated in the relative section of the AWK's user guide. Just after loading the spawk extension, the BEGIN section follows. Our test data files contain lines of tab separated fields, so we set the input fields separator to the tab character. Afterwards follows the spawk_sesami array setup, where the database access credentials are set in order to use them later, whenever a database access is needed to start a new client.

Filtering user data

...
NF == 7 {
	nf = 1
	login = $(nf++)
	registration = $(nf++)
	name = $(nf++)
	email = $(nf++)
	gender = $(nf++)
	byear = $(nf++)
	password = $(nf++)

	email = email ? spawk_escape(email) : "NULL"
	gender = gender ? spawk_escape(gender) : "NULL"
	byear = byear ? byear : "NULL"
...

This part of the script uses AWK pattern NF == 7 to filter input lines containing just 7 fields, namely the login name, the registration timestamp, the full name, the email address, the gender, the birth year and the password (in SHA1 form), from the user.data file. The email, gender and byear fields are allowed to be of null value, so we set these values to the string NULL whenever these fields are empty.

Submitting queries

...
if (spawk_submit("INSERT INTO `user` (" \
	"`login`, " \
	"`registration`, " \
	"`name`, " \
	"`email`, " \
	"`gender`, " \
	"`byear`, " \
	"`password`" \
") VALUES (" \
	spawk_escape(login) ", " \
	"FROM_UNIXTIME(" registration "), " \
	spawk_escape(name) ", " \
	email ", " \
	gender ", " \
	byear ", " \
	spawk_escape(password) \
")"))
next

if (!(++ucount % 1000))
print ucount, "users inserted"

next
...

The above script section is the first SQL script to be submitted from AWK via the SPAWK API. The function spawk_submit takes a string argument, that is the query to be submitted to the MySQL/MariaDB database server. The specific SQL script is a DML script; DML stands for Data Manipulation Language (INSERT, UPDATE, DELETE etc) in contradistinction with DQL which stands for Data Query Language (SELECT, SHOW etc).

DML queries don't produce any result rows, while DQL queries produce result rows. When submitting a query via spawk_submit function, a value is returned to the caller; a value of 0 means that the query was processed successfully, while non-zero values signal query failure. This way one can check the returned value in order to proceed with further actions or not. In our case we skip to the next input line on failure, othewise we increment a counter (ucount) and print a porogress message for every 1000 users successfully inserted. Of course, the fact that some of the user lines may fail to be inserted into the database, will cause problems later during the insertion of the relationships involving the rejected users.

...
NF == 3 {
	if (spawk_submit("INSERT INTO `relation` (" \
		"`user`, " \
		"`related`, " \
		"`relationship`" \
	") VALUES (" \
		spawk_escape($1) ", " \
		spawk_escape($2) ", " \
		spawk_escape($3) \
	")"))
	next

	if (!(++rcount % 1000))
	print rcount, "relations inserted"

	next
}
...

The above section refers to lines with 3 fields, that is lines of the relation.data file which contains 30000 user relationships. For such lines an insertion SQL query is submitted, just as we did with the user lines, and if the insertion fails we skip to the next input line, else another counter is incremented and a progress message is printed every 1000 relationship rows inserted successfully.

{
	print $0 ": syntax error" >"dev/stderr"
}

The last part of the script has nothing to do with SPAWK but it's good to catch up input lines that do not conform to the given patterns of 7 and 3 fields per line. Now it's time to actually run the script and populate the database:

awk -f populate.awk user.data relation.data
1000 users inserted 2000 users inserted 1000 relations inserted 2000 relations inserted 3000 relations inserted ... 29000 relations inserted 30000 relations inserted

That's it! Our chat database has just been populated with 2000 users and 30000 relationships, so let the games begin!

Counting users, relationships etc

Now that our chat database is populated with enough users and rleationships, we can run SPAWK scripts in order to obtain useful information. Most of this information can be extracted using plain vanilla SQL scripts, or other methods such as PHP MySQL API, Node.js etc, but SPAWK may save you a lot of time if you know how to use AWK effectively.

Counting genders

For start let's count male and female users using plain SQL:

SELECT `gender`, COUNT(*)
FROM `user`
GROUP BY `gender`
;

Download

Use the standard MySQL/MariaDB database client mysql to run the above script:

mysql --user="chat" --password="xxx" chat <gender.sql

and produce the following results:

gender	COUNT(*)
NULL	153
MALE	925
FEMALE	922

That is 925 male users, 922 female users and 153 users that have not specified their gender. Now let's submit the very same query via SPAWK:

@load "spawk"

BEGIN {
	spawk_sesami["dbuser"] = "chat"
	spawk_sesami["dbpassword"] = "xxx"
	spawk_sesami["dbname"] = "chat"

	spawk_submit("SELECT `gender`, COUNT(*) FROM `user` GROUP BY `gender`", 0)

	while (spawk_fetchrow(count))
	print count[0]
}

Download

Running the above script with SPAWK:

awk -f gender.awk

produces the following results:

	153
MALE	925
FEMALE	922

Counting relationships by gender

As you might have been thinking, it's not of much use to run SPAWK instead of plain SQL just to count users by gender. The results are the same and we used SPAWK just to submit a query and display the result rows. But what if we make our query a little harder for plain SQL to carry out? Assume for example that we want to count relationships grouped by users' gender. Unless you are some kind of SQL wizard, you may find it difficult to produce that kind of report using plain SQL. So let's try SPAWK instead:

@load "spawk"

BEGIN {
	OFS = "\t"

	spawk_sesami["dbuser"] = "chat"
	spawk_sesami["dbpassword"] = "xxx"
	spawk_sesami["dbname"] = "chat"

	spawk_submit("SELECT `login`, `gender` FROM `user`")

	while (spawk_fetchrow(user)) {
		spawk_submit("SELECT COUNT(*) FROM `relation` " \
			"WHERE `user` = " spawk_escape(user[1]))
		spawk_fetchone(relcnt)
		count[user[2]] += relcnt[1]
	}

	for (gender in count)
	print gender, count[gender]
}

Download

Run the above script with SPAWK:

awk -f relgender.awk

and you'll get the following results:

	2327
MALE	13936
FEMALE	13737

Counting friends/blocked relationships by gender

Let's make it even harder by adding the relatioship kind to the previous report. We don't want just how many relationships exist for the two genders, but we also want the kind of those relations.

@load "spawk"

BEGIN {
	OFS = "\t"

	spawk_sesami["dbuser"] = "chat"
	spawk_sesami["dbpassword"] = "xxx"
	spawk_sesami["dbname"] = "chat"

	spawk_submit("SELECT `login`, `gender` FROM `user`")

	while (spawk_fetchrow(user)) {
		spawk_submit("SELECT `relationship`, COUNT(*) " \
			"FROM `relation` WHERE `user` = " \
			spawk_escape(user[1]) " GROUP BY `relationship`")
		while (spawk_fetchrow(fbcnt))
		count[user[2] OFS fbcnt[1]] += fbcnt[2]
	}

	for (fbgender in count)
	print fbgender, count[fbgender]
}

Download

After running the above script with SPAWK we get the following results:

	BLOCKED	893
	FRIEND	1434
MALE	FRIEND	8318
MALE	BLOCKED	5618
FEMALE	FRIEND	8177
FEMALE	BLOCKED	5560

Popular and toxic users

We are now going to write a SPAWK script that scans user login names and prints popular users to the standard output sorted by popularity. Users considered popular if they have been marked more times as friend than as blocked by other users. Popularity is the count of friend type relationships for a given user.

@load "spawk"

BEGIN {
	OFS = "\t"

	spawk_sesami["dbuser"] = "chat"
	spawk_sesami["dbpassword"] = "xxx"
	spawk_sesami["dbname"] = "chat"

	spawk_submit("SELECT `login` FROM `user`")

	while (spawk_fetchrow(user))
	process_user(user[1])
}

function process_user(login,		relation, count) {
	spawk_submit("SELECT `relationship` FROM `relation` " \
		"WHERE `related` = " spawk_escape(login))

	while (spawk_fetchrow(relation))
	count[relation[1]]++

	if (count["FRIEND"] > count["BLOCKED"])
	print login, count["FRIEND"] | "sort -k2n"
}

Download

After running the above script with SPAWK we get the following results:

acasley1u	3
glilleee	3
alinnitthk	4
cfarhertyb	4
...
jmcgraead	18
bbetje58	19
glaurentmq	19
rgagenfe	19
rvagg28		19
twickesb2	19
pcamamilena	23

To print toxic users instead of popular ones, just change the last lines to:

...
if (count["FRIEND"] < count["BLOCKED"])
print login, count["BLOCKED"] | "sort -k2n"
...

Filtering popular/toxic users

Now it's time to write a filter for filtering login user names supplied as the first input field, in order to print only popular or only toxic users. By default our script will filter popular users read from the input stream; to print the toxic users we must use some kind of a flag variable.

@load "spawk"

BEGIN {
	OFS = "\t"

	spawk_sesami["dbuser"] = "chat"
	spawk_sesami["dbpassword"] = "xxx"
	spawk_sesami["dbname"] = "chat"

	# Flag "poptox" is either "popular" or "toxic" and
	# can be specified in the command line. In case not
	# specified, then "poptox" is considered "popular".

	if (!poptox)
	poptox = "popular"
}

{
	delete count

	spawk_submit("SELECT `relationship` FROM `relation` " \
		"WHERE `related` = " spawk_escape($1))

	while (spawk_fetchrow(relation))
	count[relation[1]]++

	if (poptox == "popular")
	dif = count["FRIEND"] - count["BLOCKED"]

	else
	dif = count["BLOCKED"] - count["FRIEND"]

	if (dif > 0)
	print
}

Download

To filter popular users read from standard input, run:

awk -f poptox.awk

or

awk -v poptox="popular" -f poptox.awk

The program reads login names from the input, so you have to supply login names in order to get results in the output. We don't have any convenient list of login names to test our program, so let's create one:

@include "spawk.awk"

BEGIN {
	spawk_sesami("chat", "xxx", "chat")
	spawk_submit("SELECT `login`, UNIX_TIMESTAMP(`registration`) FROM `user`")
	while (spawk_fetchrow(user)) {
		if ((user[2] % 100) > 95)
		print user[1]
	}
}

Download

We use the registration date as an epoch timestamp to filter a random set of user login names:

awk -f urand.awk >test1

Running the above script gives a total of 69 user login names in the file test1.

Let's dance!

To filter out the popular users from the test1 file:

awk -f poptox.awk test1

There exist 53 popular users in our list. For the toxic users run:

awk -v poptox="toxic" -f poptox.awk test1

There are just 11 toxic users in the list. Let's use comm to check the results:

comm -12 <(awk -f poptox.awk test1 | sort) <(awk -v poptox="toxic" -f poptox.awk test1 | sort)

We see no results, so there are exist no users filtered both as popular or as toxic by the poptox.awk script and that's a good sign. No let's extract the users of the test1 list that didn't filtered neither as popular nor as toxic users:

comm -23 <(sort test1) <(sort <(awk -f poptox.awk test1) <(awk -v poptox="toxic" -f poptox.awk test1))

And voilĂ ! The five missing users are:

abisgrovenp
ajzhakovdp
gcoramk9
hjozsefd
ksummerill4x

Astern propulsion

Now let's use SPAWK one more time to check the relationships of those low profile users that seem to have equal number of friends and blockers:

@load "spawk"

BEGIN {
	OFS = "\t"

	spawk_sesami["dbuser"] = "chat"
	spawk_sesami["dbpassword"] = "xxx"
	spawk_sesami["dbname"] = "chat"
}

{
	delete count

	spawk_submit("SELECT `relationship` FROM `relation` " \
		"WHERE `related` = " spawk_escape($1))

	while (spawk_fetchrow(relation))
	count[relation[1]]++

	print $1, count["FRIEND"], count["BLOCKED"]
}

Download

Running the above script for the five non popular neither toxic users found in our list, we get the expected results of equal number of friend/blocked relationships for each one of these users:

abisgrovenp	9	9
ajzhakovdp	5	5
gcoramk9	10	10
hjozsefd	8	8
ksummerill4x	10	10

Recreating the chat database with SPAWK

Now it's time to use SPAWK for submitting DDL queries. For this we recreate the chat database using SPAWK. As you might have already noticed, the schema.sql file follows a simple rule: the query terminator character ";" is always placed at a line by itself. Following this simple rule we can write a SPAWK script to create the chat database and the relevant database users:

@load "spawk"

# We intend to create a new database, so we have to use an administrative
# database account.

BEGIN {
	spawk_sesami["dbuser"] = "root"
	spawk_sesami["dbpassword"] = spawk_getpass("Enter root password: ")
}

# Skip blank lines.

/^[[:space:]]*$/ {
	next
}

# Skip comment lines.

/^[[:space:]]*--.*$/ {
	next
}

# Line containing just a ";" character are considered to be query
# terminators, so run the query constructed already.

/^[[:space:]]*;[[:space:]]*$/ {
	spawk_submit(query)

	# After submitting the query, reset the query to an empty string.

	query = ""
	next
}

# Add this line to the current query.

{
	query = query " " $0
}

Download

Run the above query using SPAWK:

awk -f create.awk schema.sql

and populate the database:

awk -f populate.awk user.data relation.data

Apr 03, 2022