Port bun-mariadb schema guard, targetId fix, lazy init and tests

- schema: add --dry-run (sync in a rolled-back transaction) and require
  confirmation (or --yes) before dropping tables or columns; unapproved
  destructive changes are refused
- only rebuild tables whose CREATE TABLE statement changed
- always AND targetId with the query, regardless of searchOperator
- empty IN / NOT IN lists become 1 = 0 / 1 = 1
- initialize lazily on first call so importing never throws
- read CLI version from package.json, chmod CLI on compile, pin @types/bun
- add SQL generator, value and schema guard tests

Co-Authored-By: Claude Opus 5.5 <[email protected]>

README.md

@@ -32,6 +32,7 @@ A schema-driven SQLite manager for [Bun](https://bun.sh), featuring automatic sc
 - [TypeScript Type Generation](#typescript-type-generation)
 - [Default Fields](#default-fields)
 - [Project Structure](#project-structure)
+- [Testing](#testing)
 
 ---
 
@@ -272,6 +273,8 @@ bunx bun-sqlite schema [options]
 | ----------------- | ---------------------------------------------------------- |
 | `-v`, `--vector`  | Drop and recreate all vector (`sqlite-vec`) virtual tables |
 | `-t`, `--typedef` | Also generate TypeScript type definitions after syncing    |
+| `--dry-run`       | Print the planned schema changes without applying them     |
+| `-y`, `--yes`     | Apply destructive changes (dropped tables / columns) without confirmation |
 
 **Examples:**
 
@@ -284,8 +287,13 @@ bunx bun-sqlite schema --typedef
 
 # Sync schema, recreate vector tables, and regenerate types
 bunx bun-sqlite schema --vector --typedef
+
+# Review planned changes first
+bunx bun-sqlite schema --dry-run
 ```
 
+Only tables whose definition changed are rebuilt. Changes that discard data (dropping a table, or a column removed from the schema) are listed and need confirmation before they run. Non-interactive runs (CI, scripts) refuse them unless `--yes` is passed. The plan is exact: `--dry-run` runs the whole sync in a transaction and rolls it back.
+
 ### `typedef` — Generate TypeScript types only
 
 ```bash
@@ -844,6 +852,16 @@ bun-sqlite/
 
 ---
 
+## Testing
+
+```bash
+bun run test
+```
+
+Runs the unit tests (`tests/`) and the schema sync tests (`src/lib/schema/*.test.ts`) against in-memory SQLite databases. No setup needed.
+
+---
+
 ## License
 
 MIT

bun.lock

@@ -13,7 +13,7 @@
         "sqlite-vec": "^0.1.7-alpha.2",
       },
       "devDependencies": {
-        "@types/bun": "latest",
+        "@types/bun": "1.3.14",
         "@types/inquirer": "^9.0.9",
         "@types/lodash": "^4.17.24",
         "@types/node": "^25.3.3",
@@ -56,7 +56,7 @@
 
     "@inquirer/type": ["@inquirer/[email protected]", "", { "peerDependencies": { "@types/node": ">=18" }, "optionalPeers": ["@types/node"] }, "sha512-PamArxO3cFJZoOzspzo6cxVlLeIftyBsZw/S9bKY5DzxqJVZgjoj1oP8d0rskKtp7sZxBycsoer1g6UeJV1BBA=="],
 
-    "@types/bun": ["@types/[email protected].9", "", { "dependencies": { "bun-types": "1.3.9" } }, "sha512-KQ571yULOdWJiMH+RIWIOZ7B2RXQGpL1YQrBtLIV3FqDcCu6FsbFUBwhdKUlCKUpS3PJDsHlJ1QKlpxoVR+xtw=="],
+    "@types/bun": ["@types/[email protected].14", "", { "dependencies": { "bun-types": "1.3.14" } }, "sha512-h1hFqFVcvAvD9j9K7ZW7vd82aSA+rTdznZa+5bwvCwqSB1jmmfLcbIWhOLx1/+boy/xmjgCs/OMUL8hRJSmnPw=="],
 
     "@types/inquirer": ["@types/[email protected]", "", { "dependencies": { "@types/through": "*", "rxjs": "^7.2.0" } }, "sha512-/mWx5136gts2Z2e5izdoRCo46lPp5TMs9R15GTSsgg/XnZyxDWVqoVU3R9lWnccKpqwsJLvRoxbCjoJtZB7DSw=="],
 
@@ -66,7 +66,7 @@
 
     "@types/through": ["@types/[email protected]", "", { "dependencies": { "@types/node": "*" } }, "sha512-HsJ+z3QuETzP3cswwtzt2vEIiHBk/dCcHGhbmG5X3ecnwFD/lPrMpliGXxSCg03L9AhrdwA4Oz/qfspkDW+xGQ=="],
 
-    "bun-types": ["[email protected].9", "", { "dependencies": { "@types/node": "*" } }, "sha512-+UBWWOakIP4Tswh0Bt0QD0alpTY8cb5hvgiYeWCMet9YukHbzuruIEeXC2D7nMJPB12kbh8C7XJykSexEqGKJg=="],
+    "bun-types": ["[email protected].14", "", { "dependencies": { "@types/node": "*" } }, "sha512-4N0ig0fEomHt5R0KCFWjovxow98rIoRwKolrYdCcknNwMekCXRnWEUvgu5soYV8QXtVsrUD8B95MBOZGPvr6KQ=="],
 
     "chalk": ["[email protected]", "", {}, "sha512-7NzBL0rN6fMUW+f7A6Io4h40qQlG+xGmtMxfbnH/K7TAtt8JQWVQK+6g0UXKMeVJoyV5EkkNsErQ8pVD3bLHbA=="],
 

package.json

@@ -26,13 +26,13 @@
     },
     "scripts": {
         "dev": "tsc --watch",
-        "compile": "rm -rf dist tsconfig.tsbuildinfo && tsc -p tsconfig.json",
+        "compile": "rm -rf dist tsconfig.tsbuildinfo && tsc -p tsconfig.json && chmod +x dist/commands/index.js",
         "typecheck": "tsc -p tsconfig.json --noEmit",
-        "test": "bun test src",
+        "test": "bun test src tests",
         "prepublishOnly": "bun run compile"
     },
     "devDependencies": {
-        "@types/bun": "latest",
+        "@types/bun": "1.3.14",
         "@types/inquirer": "^9.0.9",
         "@types/lodash": "^4.17.24",
         "@types/node": "^25.3.3"

src/commands/index.ts

@@ -9,6 +9,7 @@ import exportCmd from "./export";
 import importCmd from "./import";
 import admin from "./admin";
 import init from "../functions/init";
+import { readFileSync } from "fs";
 
 try {
     init();
@@ -17,13 +18,18 @@ try {
     process.exit(1);
 }
 
+/** Resolves to the package root from both src/commands and dist/commands */
+const { version } = JSON.parse(
+    readFileSync(new URL("../../package.json", import.meta.url), "utf-8"),
+);
+
 /**
  * # Describe Program
  */
 program
     .name(`bun-sqlite`)
     .description(`SQLite manager for Bun`)
-    .version(`1.0.0`);
+    .version(version);
 
 /**
  * # Declare Commands

src/commands/schema.ts

@@ -9,6 +9,8 @@ import { writeLiveSchema } from "../functions/live-schema";
 import grabDBDir from "../utils/grab-db-dir";
 import snapshotDb from "../utils/snapshot-db";
 import replaceDbFile from "../utils/replace-db-file";
+import { confirm } from "@inquirer/prompts";
+import type { SchemaChange } from "../types";
 
 export default function () {
     return new Command("schema")
@@ -18,6 +20,14 @@ export default function () {
             "Recreate Vector Tables. This will drop and rebuild all vector tables",
         )
         .option("-t, --typedef", "Generate typescript type definitions")
+        .option(
+            "--dry-run",
+            "Print the schema changes that would be applied, without applying them",
+        )
+        .option(
+            "-y, --yes",
+            "Apply destructive changes (dropped tables / columns) without confirmation",
+        )
         .action(async (opts) => {
             console.log(`Starting process ...`);
 
@@ -27,9 +37,6 @@ export default function () {
             const { ROOT_DIR, BUN_SQLITE_TEMP_DB_FILE_PATH } = grabDirNames();
             const { db_file_path } = grabDBDir({ config });
 
-            snapshotDb({ db: DbClient, dst: BUN_SQLITE_TEMP_DB_FILE_PATH });
-
-            try {
             const isVector = Boolean(opts.vector || opts.v);
             const isTypeDef = Boolean(opts.typedef || opts.t);
 
@@ -37,10 +44,86 @@ export default function () {
                 dbSchema,
             });
 
-                createDBSchema({
+            const params = {
                 db: DbClient,
                 db_schema: finaldbSchema,
                 recreate_vector_table: isVector,
+            };
+
+            /**
+             * Plan: run the sync in a transaction that is rolled back
+             */
+            const plan: SchemaChange[] = [];
+
+            try {
+                createDBSchema({ ...params, dry_run: true, changes: plan });
+            } catch (error: any) {
+                console.error(chalk.red(`Schema sync ERROR => ${error.message}`));
+                process.exit(1);
+            }
+
+            const destructive = plan.filter((change) => change.destructive);
+
+            if (opts.dryRun) {
+                if (!plan.length) {
+                    console.log(chalk.green(`Schema is up to date.`));
+                } else {
+                    console.log(chalk.bold(`Planned schema changes:\n`));
+                    for (const change of plan) {
+                        console.log(
+                            change.destructive
+                                ? chalk.red(`  ${change.description}`)
+                                : `  ${change.description}`,
+                        );
+                    }
+                    if (destructive.length) {
+                        console.log(
+                            chalk.red(
+                                `\n${destructive.length} destructive change(s) (in red) would discard data.`,
+                            ),
+                        );
+                    }
+                }
+                process.exit(0);
+            }
+
+            if (destructive.length && !opts.yes) {
+                console.log(
+                    chalk.yellow(`\nThese changes will permanently discard data:\n`),
+                );
+                for (const change of destructive) {
+                    console.log(chalk.red(`  ${change.description}`));
+                }
+                console.log();
+
+                if (!process.stdin.isTTY) {
+                    console.error(
+                        chalk.red(
+                            `Refusing to apply destructive changes non-interactively. Re-run with --yes to apply them.`,
+                        ),
+                    );
+                    process.exit(1);
+                }
+
+                const proceed = await confirm({
+                    message: `Apply ${destructive.length} destructive change(s)?`,
+                    default: false,
+                });
+
+                if (!proceed) {
+                    console.log(chalk.dim(`Schema sync cancelled.`));
+                    process.exit(1);
+                }
+            }
+
+            snapshotDb({ db: DbClient, dst: BUN_SQLITE_TEMP_DB_FILE_PATH });
+
+            try {
+                createDBSchema({
+                    ...params,
+                    allow_destructive: opts.yes
+                        ? true
+                        : new Set(destructive.map((c) => c.description)),
                 });
 
                 DbClient.close();

src/index.ts

@@ -7,16 +7,25 @@ import DbUpdate from "./lib/sqlite/db-update";
 import grabDbSchema from "./utils/grab-db-schema";
 import grabJoinFieldsFromQueryObject from "./utils/grab-join-fields-from-query-object";
 
-init();
+/**
+ * Initialize lazily on first call, so importing the library never throws.
+ * Setup errors (missing config / schema) reject the call instead.
+ */
+function withInit<F extends (...args: any[]) => Promise<any>>(fn: F): F {
+    return (async (...args: Parameters<F>) => {
+        init();
+        return fn(...args);
+    }) as F;
+}
 
 const BunSQLite = {
-    select: DbSelect,
+    select: withInit(DbSelect),
-    insert: DbInsert,
+    insert: withInit(DbInsert),
-    update: DbUpdate,
+    update: withInit(DbUpdate),
-    delete: DbDelete,
+    delete: withInit(DbDelete),
-    sql: DbSQL,
+    sql: withInit(DbSQL),
     utils: {
-        grab_db_schema: grabDbSchema,
+        grab_db_schema: withInit(grabDbSchema),
         grab_join_fields_from_query_object: grabJoinFieldsFromQueryObject,
     },
 } as const;

src/lib/schema/build-create-table-sql.ts

@@ -0,0 +1,54 @@
+import type {
+    BUN_SQLITE_DatabaseSchemaType,
+    BUN_SQLITE_TableSchemaType,
+} from "../../types";
+import { sqlQuoteIdent as q } from "../../utils/sql-safe";
+import buildColumnDefinition from "./build-column-definition";
+import buildForeignKeyConstraint from "./build-foreign-key-constraint";
+import resolveTable from "./resolve-table";
+
+type Params = {
+    db_schema: BUN_SQLITE_DatabaseSchemaType;
+    table: BUN_SQLITE_TableSchemaType;
+};
+
+/**
+ * Build the `CREATE TABLE` (or `CREATE VIRTUAL TABLE`) statement for a table
+ */
+export default function buildCreateTableSql({ db_schema, table }: Params) {
+    const new_table = resolveTable({ table, db_schema });
+
+    const columns: string[] = [];
+    const foreignKeys: string[] = [];
+
+    for (const field of new_table.fields) {
+        columns.push(buildColumnDefinition(field, new_table.isVector));
+
+        if (field.foreignKey && !new_table.isVector) {
+            foreignKeys.push(buildForeignKeyConstraint(field));
+        }
+    }
+
+    // Add unique constraints
+    for (const constraint of new_table.uniqueConstraints || []) {
+        if (!constraint.constraintTableFields?.length) continue;
+
+        const fieldNames = constraint.constraintTableFields.map((f) =>
+            String(f.value),
+        );
+        const constraintName =
+            constraint.constraintName || `unique_${fieldNames.join(", ")}`;
+
+        columns.push(
+            `CONSTRAINT ${q(constraintName)} UNIQUE (${fieldNames
+                .map(q)
+                .join(", ")})`,
+        );
+    }
+
+    const allConstraints = [...columns, ...foreignKeys];
+
+    return new_table.isVector
+        ? `CREATE VIRTUAL TABLE ${q(new_table.tableName)} USING ${new_table.vectorType || "vec0"}(${allConstraints.join(", ")})`
+        : `CREATE TABLE ${q(new_table.tableName)} (${allConstraints.join(", ")})`;
+}

src/lib/schema/create-db-schema.test.ts

@@ -3,6 +3,7 @@ import { Database } from "bun:sqlite";
 import type {
     BUN_SQLITE_FieldSchemaType,
     BUN_SQLITE_TableSchemaType,
+    SchemaChange,
 } from "../../types";
 import createDBSchema from "./create-db-schema";
 
@@ -38,8 +39,13 @@ const posts: BUN_SQLITE_TableSchemaType = {
 
 let db: Database;
 
-function sync(tables: BUN_SQLITE_TableSchemaType[]) {
+function sync(
-    createDBSchema({ db, db_schema: { tables } });
+    tables: BUN_SQLITE_TableSchemaType[],
+    options: { dry_run?: boolean; allow_destructive?: true | Set<string> } = {},
+) {
+    const changes: SchemaChange[] = [];
+    createDBSchema({ db, db_schema: { tables }, changes, ...options });
+    return changes.map((c) => (c.destructive ? `! ${c.description}` : c.description));
 }
 
 function tableNames() {
@@ -143,4 +149,48 @@ describe("createDBSchema", () => {
             ),
         ).toEqual(["id", "name"]);
     });
+
+    test("leaves unchanged tables alone", () => {
+        sync([users, posts]);
+
+        expect(sync([users, posts])).toEqual([]);
+    });
+
+    test("records changes, marking data loss as destructive", () => {
+        sync([users, posts]);
+
+        expect(
+            sync([{ ...users, fields: [id, { fieldName: "email", dataType: "TEXT" }] }]),
+        ).toEqual([
+            `Rebuild table "users"`,
+            `! Drop column "users"."name"`,
+            `! Drop table "posts"`,
+        ]);
+    });
+
+    test("dry run changes nothing", () => {
+        sync([users, posts]);
+        db.run(`INSERT INTO users (name) VALUES ('ada')`);
+
+        expect(sync([], { dry_run: true })).toEqual([
+            `! Drop table "users"`,
+            `! Drop table "posts"`,
+        ]);
+        expect(tableNames()).toEqual(["posts", "users"]);
+        expect(db.query(`SELECT name FROM users`).all()).toEqual([
+            { name: "ada" },
+        ]);
+    });
+
+    test("refuses unapproved destructive changes and rolls back", () => {
+        sync([users, posts]);
+
+        expect(() =>
+            sync([users], { allow_destructive: new Set() }),
+        ).toThrow(/Refusing unapproved destructive change/);
+        expect(tableNames()).toEqual(["posts", "users"]);
+
+        sync([users], { allow_destructive: new Set([`Drop table "posts"`]) });
+        expect(tableNames()).toEqual(["users"]);
+    });
 });

src/lib/schema/create-db-schema.ts

@@ -8,21 +8,15 @@ import orderDBSchema from "./order-db-schema";
 
 /**
  * # Sync the database to the schema
- * @description Tables are rebuilt by copying into a new table and dropping
+ * @description Changed tables are rebuilt by copying into a new table and
- * the old one. With foreign keys ON, `DROP TABLE` runs an implicit
+ * dropping the old one. With foreign keys ON, `DROP TABLE` runs an implicit
  * `DELETE FROM` that fires `ON DELETE CASCADE` on child tables, so keys are
  * disabled for the sync and checked before committing. (`PRAGMA
- * foreign_keys` is a no-op inside a transaction.)
+ * foreign_keys` is a no-op inside a transaction.) With `dry_run` the
+ * transaction is rolled back, so `changes` is the exact plan.
  */
 export default function createDBSchema(params: CreateDBSchemaParams) {
-    const { db } = params;
+    const { db, dry_run } = params;
-
-    console.log("Starting schema synchronization...");
-
-    /**
-     * Create Schema Manager Table
-     */
-    createDBManagerTable({ db });
 
     /**
      * Reorder Tables (parents before children with FKs)
@@ -33,6 +27,11 @@ export default function createDBSchema(params: CreateDBSchemaParams) {
     db.run("BEGIN");
 
     try {
+        /**
+         * Create Schema Manager Table
+         */
+        createDBManagerTable({ db });
+
         const existing_tables = getExistingTablesFromTablesManagerTable({
             db,
         });
@@ -53,7 +52,7 @@ export default function createDBSchema(params: CreateDBSchemaParams) {
          * Drop tables that no longer exist in schema
          */
         dropRemovedTables({
-            db,
+            ...params,
             existing_tables,
             schema_tables: db_schema.tables.map((t) => t.tableName),
         });
@@ -72,13 +71,11 @@ export default function createDBSchema(params: CreateDBSchemaParams) {
             );
         }
 
-        db.run("COMMIT");
+        db.run(dry_run ? "ROLLBACK" : "COMMIT");
     } catch (error) {
         if (db.inTransaction) db.run("ROLLBACK");
         throw error;
     } finally {
         db.run("PRAGMA foreign_keys = ON;");
     }
-
-    console.log("Schema synchronization complete!");
 }

src/lib/schema/create-table.ts

@@ -2,10 +2,8 @@ import type {
     BUN_SQLITE_TableSchemaType,
     CreateDBSchemaParams,
 } from "../../types";
-import { sqlQuoteIdent as q } from "../../utils/sql-safe";
+import buildCreateTableSql from "./build-create-table-sql";
-import buildColumnDefinition from "./build-column-definition";
+import recordSchemaChange from "./record-schema-change";
-import buildForeignKeyConstraint from "./build-foreign-key-constraint";
-import resolveTable from "./resolve-table";
 
 type Params = CreateDBSchemaParams & {
     table: BUN_SQLITE_TableSchemaType;
@@ -14,46 +12,12 @@ type Params = CreateDBSchemaParams & {
 /**
  * Create a new table
  */
-export default function createTable({ db, db_schema, table }: Params) {
+export default function createTable(params: Params) {
-    if (!table.tableName.match(/_temp_\d+$/)) {
+    const { db, db_schema, table } = params;
-        console.log(`Creating table: ${table.tableName}`);
-    }
 
-    const new_table = resolveTable({ table, db_schema });
+    recordSchemaChange(params, {
+        description: `Create table "${table.tableName}"`,
+    });
 
-    const columns: string[] = [];
+    db.run(buildCreateTableSql({ db_schema, table }));
-    const foreignKeys: string[] = [];
-
-    for (const field of new_table.fields) {
-        columns.push(buildColumnDefinition(field, new_table.isVector));
-
-        if (field.foreignKey && !new_table.isVector) {
-            foreignKeys.push(buildForeignKeyConstraint(field));
-        }
-    }
-
-    // Add unique constraints
-    for (const constraint of new_table.uniqueConstraints || []) {
-        if (!constraint.constraintTableFields?.length) continue;
-
-        const fieldNames = constraint.constraintTableFields.map((f) =>
-            String(f.value),
-        );
-        const constraintName =
-            constraint.constraintName || `unique_${fieldNames.join(", ")}`;
-
-        columns.push(
-            `CONSTRAINT ${q(constraintName)} UNIQUE (${fieldNames
-                .map(q)
-                .join(", ")})`,
-        );
-    }
-
-    const allConstraints = [...columns, ...foreignKeys];
-
-    const sql = new_table.isVector
-        ? `CREATE VIRTUAL TABLE ${q(new_table.tableName)} USING ${new_table.vectorType || "vec0"}(${allConstraints.join(", ")})`
-        : `CREATE TABLE ${q(new_table.tableName)} (${allConstraints.join(", ")})`;
-
-    db.run(sql);
 }

src/lib/schema/drop-removed-tables.ts

@@ -1,10 +1,12 @@
-import type { Database } from "bun:sqlite";
+import _ from "lodash";
+import type { CreateDBSchemaParams } from "../../types";
 import { readLiveSchema } from "../../functions/live-schema";
 import { sqlQuoteIdent as q } from "../../utils/sql-safe";
 import removeDBManagerTable from "./remove-db-manager-table";
+import recordSchemaChange from "./record-schema-change";
+import checkIfTableExists from "./check-if-table-exists";
 
-type Params = {
+type Params = CreateDBSchemaParams & {
-    db: Database;
     existing_tables: string[];
     schema_tables: string[];
 };
@@ -12,12 +14,8 @@ type Params = {
 /**
  * Drop tables that are no longer in the schema
  */
-export default function dropRemovedTables({
+export default function dropRemovedTables(params: Params) {
-    db,
+    const { db, existing_tables, schema_tables } = params;
-    existing_tables,
-    schema_tables,
-}: Params) {
-    console.log(`Cleaning up tables ...`);
 
     const tablesToDrop = existing_tables.filter(
         (t) =>
@@ -35,8 +33,16 @@ export default function dropRemovedTables({
         }
     }
 
-    for (const tableName of tablesToDrop) {
+    for (const tableName of _.uniq(tablesToDrop)) {
-        console.log(`Dropping table: ${tableName}`);
+        if (!checkIfTableExists({ db, table_name: tableName })) {
+            removeDBManagerTable({ db, table_name: tableName });
+            continue;
+        }
+
+        recordSchemaChange(params, {
+            description: `Drop table "${tableName}"`,
+            destructive: true,
+        });
         db.run(`DROP TABLE IF EXISTS ${q(tableName)}`);
         removeDBManagerTable({ db, table_name: tableName });
     }

src/lib/schema/handle-db-schema-table.ts

@@ -5,6 +5,7 @@ import type {
 import { sqlQuoteIdent as q } from "../../utils/sql-safe";
 import createTable from "./create-table";
 import insertDBManagerTable from "./insert-db-manager-table";
+import recordSchemaChange from "./record-schema-change";
 import removeDBManagerTable from "./remove-db-manager-table";
 import syncIndexes from "./sync-indexes";
 import updateTable from "./update-table";
@@ -28,9 +29,9 @@ export default function handleDBSchemaTable(params: Params) {
         table.tableNameOld !== table.tableName &&
         existing_tables.includes(table.tableNameOld)
     ) {
-        console.log(
+        recordSchemaChange(params, {
-            `Renaming table: ${table.tableNameOld} -> ${table.tableName}`,
+            description: `Rename table "${table.tableNameOld}" -> "${table.tableName}"`,
-        );
+        });
         db.run(
             `ALTER TABLE ${q(table.tableNameOld)} RENAME TO ${q(table.tableName)}`,
         );
@@ -46,5 +47,5 @@ export default function handleDBSchemaTable(params: Params) {
         updateTable(params);
     }
 
-    syncIndexes({ db, table });
+    syncIndexes(params);
 }

src/lib/schema/record-schema-change.ts

@@ -0,0 +1,35 @@
+import type { CreateDBSchemaParams, SchemaChange } from "../../types";
+
+/**
+ * # Record a schema change before it runs
+ * @description Logs the change (unless this is a dry run) and refuses
+ * destructive changes that were not approved.
+ */
+export default function recordSchemaChange(
+    params: Pick<
+        CreateDBSchemaParams,
+        "dry_run" | "changes" | "allow_destructive"
+    >,
+    change: SchemaChange,
+) {
+    params.changes?.push(change);
+
+    if (params.dry_run) {
+        return;
+    }
+
+    const allowed = params.allow_destructive;
+
+    if (
+        change.destructive &&
+        allowed !== undefined &&
+        allowed !== true &&
+        !allowed.has(change.description)
+    ) {
+        throw new Error(
+            `Refusing unapproved destructive change: ${change.description}. Re-run with --dry-run to review, or --yes to allow it.`,
+        );
+    }
+
+    console.log(change.description);
+}

src/lib/schema/sync-indexes.ts

@@ -1,16 +1,20 @@
-import type { Database } from "bun:sqlite";
+import type {
-import type { BUN_SQLITE_TableSchemaType } from "../../types";
+    BUN_SQLITE_TableSchemaType,
+    CreateDBSchemaParams,
+} from "../../types";
 import { sqlQuoteIdent as q } from "../../utils/sql-safe";
+import recordSchemaChange from "./record-schema-change";
 
-type Params = {
+type Params = CreateDBSchemaParams & {
-    db: Database;
     table: BUN_SQLITE_TableSchemaType;
 };
 
 /**
  * Sync indexes for a table
  */
-export default function syncIndexes({ db, table }: Params) {
+export default function syncIndexes(params: Params) {
+    const { db, table } = params;
+
     if (!table.indexes || table.indexes.length === 0) {
         return;
     }
@@ -29,7 +33,9 @@ export default function syncIndexes({ db, table }: Params) {
             (idx) => idx.indexName === indexName,
         );
         if (!stillExists) {
-            console.log(`Dropping index: ${indexName}`);
+            recordSchemaChange(params, {
+                description: `Drop index "${indexName}"`,
+            });
             db.run(`DROP INDEX IF EXISTS ${q(indexName)}`);
         }
     }
@@ -41,7 +47,9 @@ export default function syncIndexes({ db, table }: Params) {
         }
 
         if (!existingIndexes.includes(index.indexName)) {
-            console.log(`Creating index: ${index.indexName}`);
+            recordSchemaChange(params, {
+                description: `Create index "${index.indexName}" on "${table.tableName}"`,
+            });
             const fields = index.indexTableFields
                 .map((f) => q(String(f)))
                 .join(", ");

src/lib/schema/update-table.ts

@@ -3,9 +3,10 @@ import type {
     CreateDBSchemaParams,
 } from "../../types";
 import { sqlQuoteIdent as q } from "../../utils/sql-safe";
+import buildCreateTableSql from "./build-create-table-sql";
 import checkIfTableExists from "./check-if-table-exists";
-import createTable from "./create-table";
 import getTableColumns from "./get-table-columns";
+import recordSchemaChange from "./record-schema-change";
 import resolveTable from "./resolve-table";
 
 type Params = CreateDBSchemaParams & {
@@ -14,36 +15,65 @@ type Params = CreateDBSchemaParams & {
 
 /**
  * # Update an existing table
- * @description SQLite has limited ALTER TABLE support, so the table is
+ * @description SQLite has limited ALTER TABLE support, so a changed table is
  * rebuilt: create a temp table with the new schema, copy the data over,
- * drop the old table and rename the temp table.
+ * drop the old table and rename the temp table. Unchanged tables are left
+ * alone.
  */
 export default function updateTable(params: Params) {
     const { db, db_schema, table } = params;
 
-    console.log(`Updating table: ${table.tableName}`);
-
     if (table.isVector) {
         recreateVectorTable(params);
         return;
     }
 
+    /**
+     * SQLite keeps the `CREATE TABLE` text (with the renamed table name), so
+     * an identical statement means the table already matches the schema.
+     */
+    const current = db
+        .query(`SELECT sql FROM sqlite_master WHERE type='table' AND name=?`)
+        .get(table.tableName) as { sql: string } | null;
+
+    if (current?.sql === buildCreateTableSql({ db_schema, table })) {
+        return;
+    }
+
     const tempTableName = `${table.tableName}_temp_${Date.now()}`;
 
     // Columns are matched by name only: SQLite converts values to the new
     // column affinity on copy, so a type change keeps the data instead of
     // silently dropping the column.
     const existingColumns = getTableColumns({ db, table_name: table.tableName });
-    const columnsToKeep = resolveTable({ table, db_schema })
+    const schemaColumns = resolveTable({ table, db_schema }).fields.map(
-        .fields.filter(
+        (f) => f.fieldName,
-            (f) =>
+    );
-                f.fieldName &&
+    const columnsToKeep = existingColumns
-                existingColumns.find((c) => c.name == f.fieldName),
+        .map((c) => c.name)
-        )
+        .filter((name) => schemaColumns.includes(name));
-        .map((f) => f.fieldName as string);
+    const columnsToDrop = existingColumns
+        .map((c) => c.name)
+        .filter((name) => !schemaColumns.includes(name));
+
+    recordSchemaChange(params, {
+        description: `Rebuild table "${table.tableName}"`,
+    });
+
+    for (const column of columnsToDrop) {
+        recordSchemaChange(params, {
+            description: `Drop column "${table.tableName}"."${column}"`,
+            destructive: true,
+        });
+    }
 
     // Create temp table with new schema
-    createTable({ ...params, table: { ...table, tableName: tempTableName } });
+    db.run(
+        buildCreateTableSql({
+            db_schema,
+            table: { ...table, tableName: tempTableName },
+        }),
+    );
 
     // Copy data if there are common columns
     if (columnsToKeep.length > 0) {
@@ -61,12 +91,16 @@ export default function updateTable(params: Params) {
  * Vector tables are only rebuilt when `recreate_vector_table` is set.
  */
 function recreateVectorTable(params: Params) {
-    const { db, table, recreate_vector_table } = params;
+    const { db, db_schema, table, recreate_vector_table } = params;
 
     if (!recreate_vector_table) {
         return;
     }
 
+    recordSchemaChange(params, {
+        description: `Recreate vector table "${table.tableName}"`,
+    });
+
     let existingRows: { [k: string]: any }[] = [];
 
     if (checkIfTableExists({ db, table_name: table.tableName })) {
@@ -77,7 +111,7 @@ function recreateVectorTable(params: Params) {
         db.run(`DROP TABLE ${q(table.tableName)}`);
     }
 
-    createTable(params);
+    db.run(buildCreateTableSql({ db_schema, table }));
 
     for (const row of existingRows) {
         const columns = Object.keys(row);

src/lib/sqlite/db-delete.ts

@@ -30,25 +30,12 @@ export default async function DbDelete<
     let sqlObj: ReturnType<typeof sqlGenerator> | null = null;
 
     try {
-        let finalQuery = query || {};
+        const finalQuery = query || {};
-
-        if (targetId !== undefined && targetId !== null && targetId !== "") {
-            finalQuery = _.merge<
-                ServerQueryParam<any>,
-                ServerQueryParam<any>,
-                ServerQueryParam<any>
-            >({}, finalQuery, {
-                query: {
-                    id: {
-                        value: String(targetId),
-                    },
-                },
-            });
-        }
 
         sqlObj = sqlGenerator({
             tableName: table,
             genObject: _.pick(finalQuery, ["query", "searchOperator"]),
+            targetId,
         });
 
         const whereClause = sqlObj.where.string;

src/lib/sqlite/db-select.ts

@@ -1,5 +1,4 @@
 import dbHandler from "../db-handler";
-import _ from "lodash";
 import type {
     APIResponseObject,
     BunSQLiteConfig,
@@ -31,25 +30,12 @@ export default async function DbSelect<
     let sqlObj: ReturnType<typeof sqlGenerator> | null = null;
 
     try {
-        let finalQuery = query || {};
+        const finalQuery = query || {};
-
-        if (targetId !== undefined && targetId !== null && targetId !== "") {
-            finalQuery = _.merge<
-                ServerQueryParam<any>,
-                ServerQueryParam<any>,
-                ServerQueryParam<any>
-            >({}, finalQuery, {
-                query: {
-                    id: {
-                        value: String(targetId),
-                    },
-                },
-            });
-        }
 
         sqlObj = sqlGenerator({
             tableName: table,
             genObject: finalQuery,
+            targetId,
         });
 
         const sql = sqlObj.string;
@@ -80,6 +66,7 @@ export default async function DbSelect<
             const count_sql_object = sqlGenerator({
                 tableName: table,
                 genObject: finalQuery,
+                targetId,
                 count,
             });
 

src/lib/sqlite/db-update.ts

@@ -37,25 +37,12 @@ export default async function DbUpdate<
     };
 
     try {
-        let finalQuery = query || {};
+        const finalQuery = query || {};
-
-        if (targetId !== undefined && targetId !== null && targetId !== "") {
-            finalQuery = _.merge<
-                ServerQueryParam<any>,
-                ServerQueryParam<any>,
-                ServerQueryParam<any>
-            >({}, finalQuery, {
-                query: {
-                    id: {
-                        value: String(targetId),
-                    },
-                },
-            });
-        }
 
         const sqlQueryObj = sqlGenerator({
             tableName: table,
             genObject: _.pick(finalQuery, ["query", "searchOperator"]),
+            targetId,
         });
 
         let values: SQLInsertGenValueType[] = [];

src/types/index.ts

@@ -1580,6 +1580,28 @@ export type CreateDBSchemaParams = {
     db: import("bun:sqlite").Database;
     db_schema: BUN_SQLITE_DatabaseSchemaType;
     recreate_vector_table?: boolean;
+    /**
+     * Run the sync inside a transaction and roll it back. The planned
+     * changes are recorded in `changes`.
+     */
+    dry_run?: boolean;
+    /**
+     * Collects every change made (or planned) by the sync
+     */
+    changes?: SchemaChange[];
+    /**
+     * Destructive changes that may run. `true` (or unset) allows all of
+     * them; otherwise only changes whose `description` is in the set.
+     */
+    allow_destructive?: true | Set<string>;
+};
+
+/**
+ * A change made by the schema sync. Destructive changes discard data.
+ */
+export type SchemaChange = {
+    description: string;
+    destructive?: boolean;
 };
 
 /**

src/utils/sql-generator-gen-search-str.ts

@@ -83,7 +83,10 @@ export default function sqlGenGenSearchStr({
             .filter(isPresent);
         const equality = queryObj.equality;
 
-        if (equality == "IN" || equality == "NOT IN") {
+        if ((equality == "IN" || equality == "NOT IN") && !rawValues.length) {
+            // Empty IN () is invalid SQL: IN matches nothing, NOT IN matches everything
+            str = equality == "IN" ? "1 = 0" : "1 = 1";
+        } else if (equality == "IN" || equality == "NOT IN") {
             str = `${finalFieldName} ${equality} (${rawValues
                 .map(() => "?")
                 .join(", ")})`;

src/utils/sql-generator.ts

@@ -18,6 +18,11 @@ type Param<T extends { [key: string]: any } = { [key: string]: any }> = {
     tableName: string;
     dbFullName?: string;
     count?: boolean;
+    /**
+     * Restrict to a single row id. Always combined with AND, regardless of
+     * `searchOperator`.
+     */
+    targetId?: number | string;
 };
 
 type Return = {
@@ -40,7 +45,12 @@ type Return = {
  */
 export default function sqlGenerator<
     T extends { [key: string]: any } = { [key: string]: any },
->({ tableName: passedTableName, genObject, count }: Param<T>): Return {
+>({
+    tableName: passedTableName,
+    genObject,
+    count,
+    targetId,
+}: Param<T>): Return {
     const tableName = sqlIdent(passedTableName, "table name");
     const finalQuery = genObject?.query ? genObject.query : undefined;
 
@@ -115,11 +125,31 @@ export default function sqlGenerator<
         (str) => typeof str == "string",
     );
 
-    let whereString = "";
+    const whereConditions: string[] = [];
 
     if (cleanedUpSearchStr?.[0]) {
         const stringOperator = sqlOperator(genObject?.searchOperator);
-        whereString = `WHERE ${cleanedUpSearchStr.join(` ${stringOperator} `)}`;
+        whereConditions.push(
+            `(${cleanedUpSearchStr.join(` ${stringOperator} `)})`,
+        );
+    }
+
+    if (targetId !== undefined && targetId !== null && targetId !== "") {
+        const id = Number(targetId);
+
+        if (!Number.isSafeInteger(id)) {
+            throw new Error(`Invalid targetId: ${JSON.stringify(targetId)}`);
+        }
+
+        whereConditions.push(`${genObject?.join ? `${tableName}.` : ""}id = ?`);
+        whereValues.push(id);
+    }
+
+    const whereString = whereConditions.length
+        ? `WHERE ${whereConditions.join(" AND ")}`
+        : "";
+
+    if (whereString) {
         queryString += ` ${whereString}`;
         sqlSearhValues.push(...whereValues);
     }

tests/sql-generator.test.ts

@@ -0,0 +1,135 @@
+import { describe, expect, test } from "bun:test";
+import sqlGenerator from "../src/utils/sql-generator";
+
+const gen = (genObject: any, extra: Record<string, any> = {}) =>
+    sqlGenerator({ tableName: "users", genObject, ...extra });
+
+describe("identifiers", () => {
+    test("binds values and keeps identifiers", () => {
+        const { string, values } = gen({ query: { email: { value: "[email protected]" } } });
+        expect(string).toBe("SELECT * FROM users WHERE (email = ?)");
+        expect(values).toEqual(["[email protected]"]);
+    });
+
+    test.each([
+        ["field name", { query: { "1=1 OR id": { value: 1 } } }],
+        ["quoted field name", { query: { 'a" OR 1=1 --': { value: 1 } } }],
+        ["select field", { selectFields: ["name; DROP TABLE users"] }],
+    ])("rejects an injected %s", (_name, genObject) => {
+        expect(() => gen(genObject)).toThrow();
+    });
+
+    test("rejects an injected table name", () => {
+        expect(() =>
+            sqlGenerator({ tableName: "users; DROP TABLE users", genObject: {} }),
+        ).toThrow();
+    });
+});
+
+describe("input validation", () => {
+    test.each([
+        ["order strategy", { order: { field: "id", strategy: "DESC; DROP TABLE x" } }],
+        ["limit", { limit: "1; --" }],
+        ["negative offset", { offset: -1 }],
+        ["page", { limit: 10, page: "2 OR 1" }],
+        ["search operator", { query: { a: { value: 1 } }, searchOperator: "OR 1=1" }],
+        ["raw equality", { query: { a: { value: 1, raw_equality: "= 1 OR" } } }],
+        ["join type", { join: [{ tableName: "p", joinType: "CROSS JOIN x;", match: { source: "id", target: "uid" } }] }],
+    ])("rejects invalid %s", (_name, genObject) => {
+        expect(() => gen(genObject)).toThrow();
+    });
+
+    test("rejects non-numeric targetId", () => {
+        expect(() => gen({}, { targetId: "abc" })).toThrow();
+    });
+});
+
+describe("targetId", () => {
+    test("is ANDed with the query, even with searchOperator OR", () => {
+        const { string, values } = gen(
+            { query: { a: { value: 1 }, b: { value: 2 } }, searchOperator: "OR" },
+            { targetId: 5 },
+        );
+        expect(string).toBe(
+            "SELECT * FROM users WHERE (a = ? OR b = ?) AND id = ?",
+        );
+        expect(values).toEqual([1, 2, 5]);
+    });
+
+    test("accepts numeric strings", () => {
+        const { string, values } = gen({}, { targetId: "7" });
+        expect(string).toBe("SELECT * FROM users WHERE id = ?");
+        expect(values).toEqual([7]);
+    });
+
+    test("0 is a real id", () => {
+        expect(gen({}, { targetId: 0 }).values).toEqual([0]);
+    });
+
+    test("is table-qualified with joins", () => {
+        const { string } = gen(
+            {
+                join: [
+                    {
+                        tableName: "posts",
+                        joinType: "LEFT JOIN",
+                        match: { source: "id", target: "user_id" },
+                    },
+                ],
+            },
+            { targetId: 3 },
+        );
+        expect(string).toEndWith("WHERE users.id = ?");
+    });
+
+    test("is part of the where clause used by update / delete", () => {
+        const { where } = gen({ query: { a: { value: 1 } } }, { targetId: 2 });
+        expect(where).toEqual({
+            string: "WHERE (a = ?) AND id = ?",
+            values: [1, 2],
+        });
+    });
+});
+
+describe("values", () => {
+    test("0 is a real value", () => {
+        expect(gen({ query: { age: { value: 0 } } }).values).toEqual([0]);
+    });
+
+    test("IN binds each value", () => {
+        const { string, values } = gen({
+            query: { id: { value: [1, 2], equality: "IN" } },
+        });
+        expect(string).toBe("SELECT * FROM users WHERE (id IN (?, ?))");
+        expect(values).toEqual([1, 2]);
+    });
+
+    test("empty IN matches nothing, empty NOT IN matches everything", () => {
+        expect(gen({ query: { id: { value: [], equality: "IN" } } }).string).toBe(
+            "SELECT * FROM users WHERE (1 = 0)",
+        );
+        expect(
+            gen({ query: { id: { value: [], equality: "NOT IN" } } }).string,
+        ).toBe("SELECT * FROM users WHERE (1 = 1)");
+    });
+
+    test("BETWEEN needs exactly two values", () => {
+        expect(() =>
+            gen({ query: { age: { value: [1], equality: "BETWEEN" } } }),
+        ).toThrow();
+    });
+});
+
+describe("pagination", () => {
+    test("page is converted to an offset", () => {
+        expect(gen({ limit: 10, page: 3 }).string).toBe(
+            "SELECT * FROM users LIMIT 10 OFFSET 20",
+        );
+    });
+
+    test("count queries skip pagination", () => {
+        expect(gen({ limit: 10, page: 3 }, { count: true }).string).not.toContain(
+            "LIMIT",
+        );
+    });
+});

tests/sql-values.test.ts

@@ -0,0 +1,61 @@
+import { describe, expect, test } from "bun:test";
+import sqlInsertGenerator, { sqlValue } from "../src/utils/sql-insert-generator";
+
+describe("sqlValue", () => {
+    test("booleans become 0 / 1", () => {
+        expect(sqlValue(false)).toBe(0);
+        expect(sqlValue(true)).toBe(1);
+    });
+
+    test("0 and empty strings are kept", () => {
+        expect(sqlValue(0)).toBe(0);
+        expect(sqlValue("")).toBe("");
+    });
+
+    test("undefined becomes NULL", () => {
+        expect(sqlValue(undefined)).toBeNull();
+    });
+});
+
+describe("sqlInsertGenerator", () => {
+    test("builds a multi-row insert", () => {
+        const res = sqlInsertGenerator({
+            tableName: "items",
+            data: [
+                { name: "a", active: false, qty: 0 },
+                { name: "b", note: "" },
+            ],
+        });
+        expect(res?.query).toBe(
+            "INSERT INTO items (name,active,qty,note) VALUES (?,?,?,?),(?,?,?,?)",
+        );
+        expect(res?.values).toEqual(["a", 0, 0, null, "b", null, null, ""]);
+    });
+
+    test("function values are called once", () => {
+        let calls = 0;
+        const res = sqlInsertGenerator({
+            tableName: "items",
+            data: [
+                {
+                    emb: () => {
+                        calls++;
+                        return { value: "[1,2]", placeholder: "vec_f32(?)" };
+                    },
+                },
+            ],
+        });
+        expect(calls).toBe(1);
+        expect(res?.query).toBe("INSERT INTO items (emb) VALUES (vec_f32(?))");
+        expect(res?.values).toEqual(["[1,2]"]);
+    });
+
+    test("rejects injected column names", () => {
+        expect(() =>
+            sqlInsertGenerator({
+                tableName: "items",
+                data: [{ "name) VALUES (1); --": "x" }],
+            }),
+        ).toThrow();
+    });
+});