diff --git a/src/datasources/lemondb/DDL.sql b/src/datasources/lemondb/DDL.sql
new file mode 100644
index 0000000..afc9661
--- /dev/null
+++ b/src/datasources/lemondb/DDL.sql
@@ -0,0 +1,89 @@
+
+SET default_tablespace = ts_lemon;
+CREATE EXTENSION IF NOT EXISTS pgcrypto;
+CREATE TABLE IF NOT EXISTS accounts
+(
+    account_id   serial PRIMARY KEY,
+    account_name varchar(255) NOT NULL,
+    login        varchar(100) NOT NULL,
+    password     varchar      NOT NULL
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS iu_accounts$login ON accounts (login) TABLESPACE ts_lemon_indexes;
+
+ALTER TABLE accounts
+    ADD CONSTRAINT ch_accounts$login
+        CHECK (login ~ '^\S+$');
+
+CREATE TABLE IF NOT EXISTS banks
+(
+    bank_id   smallserial PRIMARY KEY,
+    bank_name varchar(255) NOT NULL UNIQUE
+);
+
+CREATE TABLE IF NOT EXISTS cards
+(
+    card_id    serial PRIMARY KEY,
+    bank_id    smallint NOT NULL,
+    account_id int      NOT NULL,
+    card_num   smallint NOT NULL,
+    type       varchar(255) DEFAULT NULL,
+    balance    int      NOT NULL,
+    currency   char(3)  NOT NULL
+);
+CREATE UNIQUE INDEX IF NOT EXISTS iu_accounts$account_id_card_num ON accounts (login) TABLESPACE ts_lemon_indexes;
+ALTER TABLE cards
+    ADD CONSTRAINT ch_len_cards$card_num
+        CHECK (CHAR_LENGTH(card_num::text) BETWEEN 4 AND 16),
+    ADD CONSTRAINT ch_cards$currency
+        CHECK ( CHAR_LENGTH(currency) = 3 AND currency ~ '^\D+$'),
+    ADD CONSTRAINT ch_not_negative
+        CHECK ( card_num >= 0 ),
+    ADD CONSTRAINT fk_cards$bank_id
+        FOREIGN KEY (bank_id)
+            REFERENCES banks (bank_id) ON DELETE CASCADE ON UPDATE CASCADE,
+    ADD CONSTRAINT fk_cards$account_id
+        FOREIGN KEY (account_id)
+            REFERENCES accounts (account_id) ON DELETE CASCADE ON UPDATE CASCADE
+;
+
+CREATE INDEX IF NOT EXISTS bank_idx ON cards (bank_id) TABLESPACE ts_lemon_indexes;
+CREATE INDEX IF NOT EXISTS account_idx ON cards (account_id) TABLESPACE ts_lemon_indexes;
+
+CREATE TABLE IF NOT EXISTS transactions
+(
+    transaction_id       serial PRIMARY KEY,
+    card_id              int DEFAULT NULL,
+    amount               int NOT NULL,
+    type                 varchar(255) DEFAULT NULL,
+    transaction_datetime timestamptz DEFAULT NULL
+);
+ALTER TABLE transactions
+ADD CONSTRAINT fk_transactions$card_id
+FOREIGN KEY (card_id) REFERENCES cards (card_id) ON DELETE CASCADE ON UPDATE CASCADE,
+    ADD CONSTRAINT ch_transactions$transaction_datetime
+CHECK ( EXTRACT(YEAR FROM transaction_datetime) >=1951 );
+
+CREATE TABLE IF NOT EXISTS types
+(
+    type_id   smallserial PRIMARY KEY,
+    type_name varchar(100) NOT NULL UNIQUE
+);
+
+CREATE TABLE IF NOT EXISTS connection
+(
+    connection_id serial PRIMARY KEY,
+    card_id       int      NOT NULL,
+    type_id       smallint NOT NULL,
+    value         varchar  NOT NULL
+);
+ALTER TABLE connection
+ADD CONSTRAINT fk_connection$card_id
+FOREIGN KEY (card_id) REFERENCES cards (card_id) ON DELETE CASCADE ON UPDATE CASCADE,
+    ADD CONSTRAINT fk_connection$type_id
+    FOREIGN KEY (type_id) REFERENCES types (type_id) ON DELETE CASCADE ON UPDATE CASCADE;
+
+CREATE INDEX IF NOT EXISTS type_idx ON connection (type_id) TABLESPACE ts_lemon_indexes;
+CREATE INDEX IF NOT EXISTS card_idx ON connection (card_id) TABLESPACE ts_lemon_indexes;
+
+