Constant CATALOG_SQL 

pub const CATALOG_SQL: &str = r#"
CREATE SCHEMA IF NOT EXISTS improv;
CREATE TABLE IF NOT EXISTS improv.model (
    id        bigserial PRIMARY KEY,
    name      text NOT NULL UNIQUE,
    sync_mode text NOT NULL DEFAULT 'logical'
              CHECK (sync_mode IN ('logical', 'trigger', 'commit', 'manual')),
    slot_name text,
    created   timestamptz NOT NULL DEFAULT now()
);
CREATE TABLE IF NOT EXISTS improv.category (
    model_id bigint NOT NULL REFERENCES improv.model(id) ON DELETE CASCADE,
    id       bigint NOT NULL,
    name     text NOT NULL,
    PRIMARY KEY (model_id, id)
);
CREATE TABLE IF NOT EXISTS improv.item (
    model_id    bigint NOT NULL REFERENCES improv.model(id) ON DELETE CASCADE,
    id          bigint NOT NULL,
    category_id bigint NOT NULL,
    name        text NOT NULL,
    PRIMARY KEY (model_id, id)
);
CREATE TABLE IF NOT EXISTS improv.measure (
    model_id    bigint NOT NULL REFERENCES improv.model(id) ON DELETE CASCADE,
    id          bigint NOT NULL,
    name        text NOT NULL,
    value_type  text NOT NULL,
    kind        text NOT NULL CHECK (kind IN ('input', 'derived')),
    formula     text,
    description text,
    categories  bigint[] NOT NULL DEFAULT '{}',
    PRIMARY KEY (model_id, id)
);
CREATE TABLE IF NOT EXISTS improv.binding (
    model_id   bigint NOT NULL REFERENCES improv.model(id) ON DELETE CASCADE,
    measure_id bigint NOT NULL,
    rel        regclass NOT NULL,
    value_col  text NOT NULL,
    dim_cols   jsonb NOT NULL,
    PRIMARY KEY (model_id, measure_id)
);
CREATE TABLE IF NOT EXISTS improv.cell (
    model_id   bigint NOT NULL REFERENCES improv.model(id) ON DELETE CASCADE,
    measure_id bigint NOT NULL,
    coord      jsonb NOT NULL,
    value      jsonb NOT NULL,
    PRIMARY KEY (model_id, measure_id, coord)
);
CREATE TABLE IF NOT EXISTS improv.view (
    model_id bigint NOT NULL REFERENCES improv.model(id) ON DELETE CASCADE,
    id       bigint NOT NULL,
    name     text NOT NULL,
    layout   jsonb NOT NULL,
    PRIMARY KEY (model_id, id)
);
CREATE TABLE IF NOT EXISTS improv.meta (
    model_id bigint PRIMARY KEY REFERENCES improv.model(id) ON DELETE CASCADE,
    blob     jsonb NOT NULL
);
CREATE TABLE IF NOT EXISTS improv.model_version (
    model_id bigint PRIMARY KEY REFERENCES improv.model(id) ON DELETE CASCADE,
    tx       bigint NOT NULL DEFAULT 0
);
CREATE TABLE IF NOT EXISTS improv.lambda (
    model_id   bigint NOT NULL REFERENCES improv.model(id) ON DELETE CASCADE,
    id         bigint NOT NULL,
    name       text NOT NULL,
    definition text NOT NULL,
    PRIMARY KEY (model_id, id)
);
-- Shared with the pg_improv extension (design §9.2): the same DDL in
-- idempotent form (this runs against an existing database); the extension
-- uses plain CREATE. Both pin mint_items' search_path.
ALTER TABLE improv.binding ADD COLUMN IF NOT EXISTS agg text
  CHECK (agg IN ('sum', 'avg', 'min', 'max', 'count', 'count_distinct'));
CREATE UNIQUE INDEX IF NOT EXISTS item_name_uniq ON improv.item (model_id, category_id, name);
CREATE OR REPLACE FUNCTION improv.mint_items(p_model bigint, p_cats bigint[], p_names text[])
RETURNS TABLE (category_id bigint, name text, id bigint) LANGUAGE plpgsql
SET search_path = pg_catalog, pg_temp AS $$
BEGIN
  PERFORM 1 FROM improv.model m WHERE m.id = p_model FOR UPDATE;
  INSERT INTO improv.item (model_id, id, category_id, name)
  SELECT p_model,
         (SELECT coalesce(max(i.id), 0) FROM improv.item i WHERE i.model_id = p_model)
           + row_number() OVER (ORDER BY s.c, s.n),
         s.c, s.n
  FROM (SELECT DISTINCT u.c, u.n FROM unnest(p_cats, p_names) AS u(c, n)
        WHERE NOT EXISTS (SELECT 1 FROM improv.item i
                          WHERE i.model_id = p_model AND i.category_id = u.c AND i.name = u.n)) s
  ON CONFLICT DO NOTHING;
  RETURN QUERY
    SELECT i.category_id, i.name, i.id FROM improv.item i
    JOIN (SELECT DISTINCT u.c, u.n FROM unnest(p_cats, p_names) AS u(c, n)) w
      ON i.model_id = p_model AND i.category_id = w.c AND i.name = w.n;
END $$;
"#;

The catalog this client depends on (design §2), created when the pg_improv extension is not installed so a plain Postgres works too.

Kept in this ONE place so it can be reconciled with the extension’s own catalog SQL; nothing else in this crate issues DDL against improv.*.