class SQLiteDatabaseClient { constructor(buffer) { Object.defineProperties(this, { _db: {value: Promise.resolve(buffer).then(buffer => new SQLite(buffer))} }); } async query(sql, params) { return (await this._db).exec(sql, params); } async queryRow(sql, params) { return (await this.query(sql, params))[0]; } async explain(sql, params) { const rows = (await this.query(`EXPLAIN QUERY PLAN ${sql}`, params)); const text = rows.map(row => row.detail).join("\n"); const pre = document.createElement("PRE"); pre.className = "observablehq--inspect"; pre.appendChild(document.createTextNode(text)); return pre; } async describe(object) { if (object !== undefined) { const [row] = await this.query(`SELECT * FROM '${object}' LIMIT 1`); const value = Object.entries(row).map(([column_name, value]) => ({ column_name, data_type: typeof value === "string" ? "character varying" : typeof value === "number" ? "integer" : undefined, column_default: null, is_nullable: "YES" })); const table = html` ${value.map(({column_name, data_type, column_default, is_nullable}) => html` `)}

column_name	data_type	column_default	is_nullable
${column_name}	${data_type}	${column_default}	${is_nullable}

`; table.value = value; return table; } else { const rows = await this.query(`SELECT name FROM sqlite_master WHERE type = 'table'`); const table = html` ${rows.map(({name}) => html` `)}

name
${name}

`; table.value = [{table_schema: "public", table_name: "names"}]; return table; } } }