aljaz/turso
1
0
Fork 0
mirror of https://github.com/aljazceru/turso.git synced 2025-12-25 12:04:21 +01:00
Code Issues Packages Projects Releases Wiki Activity
Files
a4a80f37bc2775ebce032f491a1002f03aec61ba
turso/COMPAT.md
Glauber Costa a3387cfd5f implement the pragma page_count 
To do that, we also have to implement the vdbe opcode Pagecount.
2025-02-01 19:39:46 -05:00

632 lines
42 KiB
Markdown
Raw Blame History

# Compatibility with SQLite
This document describes the compatibility of Limbo with SQLite.
## Table of contents:
- [Compatibility with SQLite](#compatibility-with-sqlite)
- [Table of contents:](#table-of-contents)
- [Features](#features)
- [SQLite query language](#sqlite-query-language)
- [Statements](#statements)
- [PRAGMA](#pragma)
- [Expressions](#expressions)
- [SQL functions](#sql-functions)
- [Scalar functions](#scalar-functions)
- [Mathematical functions](#mathematical-functions)
- [Aggregate functions](#aggregate-functions)
- [Date and time functions](#date-and-time-functions)
- [JSON functions](#json-functions)
- [SQLite C API](#sqlite-c-api)
- [SQLite VDBE opcodes](#sqlite-vdbe-opcodes)
- [SQLite journaling modes](#sqlite-journaling-modes)
- [Extensions](#extensions)
- [UUID](#uuid)
- [regexp](#regexp)
## Features
Limbo aims to be fully compatible with SQLite, with opt-in features not supported by SQLite.
The current status of Limbo is:
* ✅ SQLite file format is fully supported.
* 🚧 SQLite query language [[status](#sqlite-query-language)]
* 🚧 SQLite C API [[status](#sqlite-c-api)].
* ⛔️ Concurrent access from multiple processes is not supported.
## SQLite query language
### Statements
| Statement | Status | Comment |
|---------------------------|---------|-----------------------------------------------------------------------------------|
| ALTER TABLE | No | |
| ANALYZE | No | |
| ATTACH DATABASE | No | |
| BEGIN TRANSACTION | No | |
| COMMIT TRANSACTION | No | |
| CREATE INDEX | No | |
| CREATE TABLE | Partial | |
| CREATE TRIGGER | No | |
| CREATE VIEW | No | |
| CREATE VIRTUAL TABLE | No | |
| DELETE | No | |
| DETACH DATABASE | No | |
| DROP INDEX | No | |
| DROP TABLE | No | |
| DROP TRIGGER | No | |
| DROP VIEW | No | |
| END TRANSACTION | No | |
| EXPLAIN | Yes | |
| INDEXED BY | No | |
| INSERT | Partial | |
| ON CONFLICT clause | No | |
| REINDEX | No | |
| RELEASE SAVEPOINT | No | |
| REPLACE | No | |
| RETURNING clause | No | |
| ROLLBACK TRANSACTION | No | |
| SAVEPOINT | No | |
| SELECT | Yes | |
| SELECT ... WHERE | Yes | |
| SELECT ... WHERE ... LIKE | Yes | |
| SELECT ... LIMIT | Yes | |
| SELECT ... ORDER BY | Yes | |
| SELECT ... GROUP BY | Yes | |
| SELECT ... HAVING | Yes | |
| SELECT ... JOIN | Yes | |
| SELECT ... CROSS JOIN | Yes | SQLite CROSS JOIN means "do not reorder joins". We don't support that yet anyway. |
| SELECT ... INNER JOIN | Yes | |
| SELECT ... OUTER JOIN | Partial | no RIGHT JOIN |
| SELECT ... JOIN USING | Yes | |
| SELECT ... NATURAL JOIN | Yes | |
| UPDATE | No | |
| UPSERT | No | |
| VACUUM | No | |
| WITH clause | No | |
#### [PRAGMA](https://www.sqlite.org/pragma.html)
| Statement | Status | Comment |
|----------------------------------|------------|----------------------------------------------|
| PRAGMA analysis_limit | No | |
| PRAGMA application_id | No | |
| PRAGMA auto_vacuum | No | |
| PRAGMA automatic_index | No | |
| PRAGMA busy_timeout | No | |
| PRAGMA busy_timeout | No | |
| PRAGMA cache_size | Yes | |
| PRAGMA cache_spill | No | |
| PRAGMA case_sensitive_like | Not Needed | deprecated in SQLite |
| PRAGMA cell_size_check | No | |
| PRAGMA checkpoint_fullsync | No | |
| PRAGMA collation_list | No | |
| PRAGMA compile_options | No | |
| PRAGMA count_changes | Not Needed | deprecated in SQLite |
| PRAGMA data_store_directory | Not Needed | deprecated in SQLite |
| PRAGMA data_version | No | |
| PRAGMA database_list | No | |
| PRAGMA default_cache_size | Not Needed | deprecated in SQLite |
| PRAGMA defer_foreign_keys | No | |
| PRAGMA empty_result_callbacks | Not Needed | deprecated in SQLite |
| PRAGMA encoding | No | |
| PRAGMA foreign_key_check | No | |
| PRAGMA foreign_key_list | No | |
| PRAGMA foreign_keys | No | |
| PRAGMA freelist_count | No | |
| PRAGMA full_column_names | Not Needed | deprecated in SQLite |
| PRAGMA fullsync | No | |
| PRAGMA function_list | No | |
| PRAGMA hard_heap_limit | No | |
| PRAGMA ignore_check_constraints | No | |
| PRAGMA incremental_vacuum | No | |
| PRAGMA index_info | No | |
| PRAGMA index_list | No | |
| PRAGMA index_xinfo | No | |
| PRAGMA integrity_check | No | |
| PRAGMA journal_mode | Yes | |
| PRAGMA journal_size_limit | No | |
| PRAGMA legacy_alter_table | No | |
| PRAGMA legacy_file_format | No | |
| PRAGMA locking_mode | No | |
| PRAGMA max_page_count | No | |
| PRAGMA mmap_size | No | |
| PRAGMA module_list | No | |
| PRAGMA optimize | No | |
| PRAGMA page_count | Yes | |
| PRAGMA page_size | No | |
| PRAGMA parser_trace | No | |
| PRAGMA pragma_list | Yes | |
| PRAGMA query_only | No | |
| PRAGMA quick_check | No | |
| PRAGMA read_uncommitted | No | |
| PRAGMA recursive_triggers | No | |
| PRAGMA reverse_unordered_selects | No | |
| PRAGMA schema_version | No | |
| PRAGMA secure_delete | No | |
| PRAGMA short_column_names | Not Needed | deprecated in SQLite |
| PRAGMA shrink_memory | No | |
| PRAGMA soft_heap_limit | No | |
| PRAGMA stats | No | Used for testing in SQLite |
| PRAGMA synchronous | No | |
| PRAGMA table_info | Yes | |
| PRAGMA table_list | No | |
| PRAGMA table_xinfo | No | |
| PRAGMA temp_store | No | |
| PRAGMA temp_store_directory | Not Needed | deprecated in SQLite |
| PRAGMA threads | No | |
| PRAGMA trusted_schema | No | |
| PRAGMA user_version | No | |
| PRAGMA vdbe_addoptrace | No | |
| PRAGMA vdbe_debug | No | |
| PRAGMA vdbe_listing | No | |
| PRAGMA vdbe_trace | No | |
| PRAGMA wal_autocheckpoint | No | |
| PRAGMA wal_checkpoint | Partial | Not Needed calling with param (pragma-value) |
| PRAGMA writable_schema | No | |
### Expressions
Feature support of [sqlite expr syntax](https://www.sqlite.org/lang_expr.html).
| Syntax | Status | Comment |
|---------------------------|---------|------------------------------------------|
| literals | Yes | |
| schema.table.column | Partial | Schemas aren't supported |
| unary operator | Yes | |
| binary operator | Partial | Only `%`, `!<`, and `!>` are unsupported |
| agg() FILTER (WHERE ...) | No | Is incorrectly ignored |
| ... OVER (...) | No | Is incorrectly ignored |
| (expr) | Yes | |
| CAST (expr AS type) | Yes | |
| COLLATE | No | |
| (NOT) LIKE | Yes | |
| (NOT) GLOB | Yes | |
| (NOT) REGEXP | No | |
| (NOT) MATCH | No | |
| IS (NOT) | Yes | |
| IS (NOT) DISTINCT FROM | Yes | |
| (NOT) BETWEEN ... AND ... | No | |
| (NOT) IN (subquery) | No | |
| (NOT) EXISTS (subquery) | No | |
| CASE WHEN THEN ELSE END | Yes | |
| RAISE | No | |
### SQL functions
#### Scalar functions
| Function | Status | Comment |
|------------------------------|---------|------------------------------------------------------|
| abs(X) | Yes | |
| changes() | Partial | Still need to support update statements and triggers |
| char(X1,X2,...,XN) | Yes | |
| coalesce(X,Y,...) | Yes | |
| concat(X,...) | Yes | |
| concat_ws(SEP,X,...) | Yes | |
| format(FORMAT,...) | No | |
| glob(X,Y) | Yes | |
| hex(X) | Yes | |
| ifnull(X,Y) | Yes | |
| iif(X,Y,Z) | Yes | |
| instr(X,Y) | Yes | |
| last_insert_rowid() | Yes | |
| length(X) | Yes | |
| like(X,Y) | Yes | |
| like(X,Y,Z) | Yes | |
| likelihood(X,Y) | No | |
| likely(X) | No | |
| load_extension(X) | Yes | sqlite3 extensions not yet supported |
| load_extension(X,Y) | No | |
| lower(X) | Yes | |
| ltrim(X) | Yes | |
| ltrim(X,Y) | Yes | |
| max(X,Y,...) | Yes | |
| min(X,Y,...) | Yes | |
| nullif(X,Y) | Yes | |
| octet_length(X) | Yes | |
| printf(FORMAT,...) | No | |
| quote(X) | Yes | |
| random() | Yes | |
| randomblob(N) | Yes | |
| replace(X,Y,Z) | Yes | |
| round(X) | Yes | |
| round(X,Y) | Yes | |
| rtrim(X) | Yes | |
| rtrim(X,Y) | Yes | |
| sign(X) | Yes | |
| soundex(X) | Yes | |
| sqlite_compileoption_get(N) | No | |
| sqlite_compileoption_used(X) | No | |
| sqlite_offset(X) | No | |
| sqlite_source_id() | Yes | |
| sqlite_version() | Yes | |
| substr(X,Y,Z) | Yes | |
| substr(X,Y) | Yes | |
| substring(X,Y,Z) | Yes | |
| substring(X,Y) | Yes | |
| total_changes() | Partial | Still need to support update statements and triggers |
| trim(X) | Yes | |
| trim(X,Y) | Yes | |
| typeof(X) | Yes | |
| unhex(X) | Yes | |
| unhex(X,Y) | Yes | |
| unicode(X) | Yes | |
| unlikely(X) | No | |
| upper(X) | Yes | |
| zeroblob(N) | Yes | |
#### Mathematical functions
| Function | Status | Comment |
|------------|--------|---------|
| acos(X) | Yes | |
| acosh(X) | Yes | |
| asin(X) | Yes | |
| asinh(X) | Yes | |
| atan(X) | Yes | |
| atan2(Y,X) | Yes | |
| atanh(X) | Yes | |
| ceil(X) | Yes | |
| ceiling(X) | Yes | |
| cos(X) | Yes | |
| cosh(X) | Yes | |
| degrees(X) | Yes | |
| exp(X) | Yes | |
| floor(X) | Yes | |
| ln(X) | Yes | |
| log(B,X) | Yes | |
| log(X) | Yes | |
| log10(X) | Yes | |
| log2(X) | Yes | |
| mod(X,Y) | Yes | |
| pi() | Yes | |
| pow(X,Y) | Yes | |
| power(X,Y) | Yes | |
| radians(X) | Yes | |
| sin(X) | Yes | |
| sinh(X) | Yes | |
| sqrt(X) | Yes | |
| tan(X) | Yes | |
| tanh(X) | Yes | |
| trunc(X) | Yes | |
#### Aggregate functions
| Function | Status | Comment |
|------------------------------|---------|---------|
| avg(X) | Yes | |
| count() | Yes | |
| count(*) | Yes | |
| group_concat(X) | Yes | |
| group_concat(X,Y) | Yes | |
| string_agg(X,Y) | Yes | |
| max(X) | Yes | |
| min(X) | Yes | |
| sum(X) | Yes | |
| total(X) | Yes | |
#### Date and time functions
| Function | Status | Comment |
|-------------|---------|------------------------------|
| date() | Yes | partially supports modifiers |
| time() | Yes | partially supports modifiers |
| datetime() | Yes | partially supports modifiers |
| julianday() | Partial | does not support modifiers |
| unixepoch() | Partial | does not support modifiers |
| strftime() | Yes | partially supports modifiers |
| timediff() | No | |
Modifiers:
| Modifier | Status| Comment |
|----------------|-------|---------------------------------|
| Days | Yes | |
| Hours | Yes | |
| Minutes | Yes | |
| Seconds | Yes | |
| Months | Yes | |
| Years | Yes | |
| TimeOffset | Yes | |
| DateOffset | Yes | |
| DateTimeOffset | Yes | |
| Ceiling | No | |
| Floor | No | |
| StartOfMonth | Yes | |
| StartOfYear | Yes | |
| StartOfDay | Yes | |
| Weekday(N) | Yes | |
| Auto | No | |
| UnixEpoch | No | |
| JulianDay | No | |
| Localtime |Partial| requires fixes to avoid double conversions.|
| Utc |Partial| requires fixes to avoid double conversions.|
| Subsec | Yes | |
#### JSON functions
| Function | Status | Comment |
|------------------------------------|---------|----------------------------------------------------------------------------------------------------------------------------------------------|
| json(json) | Partial | |
| jsonb(json) | | |
| json_array(value1,value2,...) | Yes | |
| jsonb_array(value1,value2,...) | | |
| json_array_length(json) | Yes | |
| json_array_length(json,path) | Yes | |
| json_error_position(json) | Yes | |
| json_extract(json,path,...) | Partial | Does not fully support unicode literal syntax and does not allow numbers > 2^127 - 1 (which SQLite truncates to i32), does not support BLOBs |
| jsonb_extract(json,path,...) | | |
| json -> path | Yes | |
| json ->> path | Yes | |
| json_insert(json,path,value,...) | | |
| jsonb_insert(json,path,value,...) | | |
| json_object(label1,value1,...) | Yes | When keys are duplicated, only the last one processed is returned. This differs from sqlite, where the keys in the output can be duplicated |
| jsonb_object(label1,value1,...) | | |
| json_patch(json1,json2) | Yes | |
| jsonb_patch(json1,json2) | | |
| json_pretty(json) | | |
| json_remove(json,path,...) | Partial | Uses same json path parser as json_extract so shares same limitations. |
| jsonb_remove(json,path,...) | | |
| json_replace(json,path,value,...) | | |
| jsonb_replace(json,path,value,...) | | |
| json_set(json,path,value,...) | | |
| jsonb_set(json,path,value,...) | | |
| json_type(json) | Yes | |
| json_type(json,path) | Yes | |
| json_valid(json) | Yes | |
| json_valid(json,flags) | | |
| json_quote(value) | | |
| json_group_array(value) | | |
| jsonb_group_array(value) | | |
| json_group_object(label,value) | | |
| jsonb_group_object(name,value) | | |
| json_each(json) | | |
| json_each(json,path) | | |
| json_tree(json) | | |
| json_tree(json,path) | | |
## SQLite C API
| Interface | Status | Comment |
|---------------------|---------|---------|
| sqlite3_open | Partial | |
| sqlite3_close | Yes | |
| sqlite3_prepare | Partial | |
| sqlite3_finalize | Yes | |
| sqlite3_step | Yes | |
| sqlite3_column_text | Yes | |
## SQLite VDBE opcodes
| Opcode | Status | Comment |
|----------------|--------|---------|
| Add | Yes | |
| AddImm | No | |
| Affinity | No | |
| AggFinal | Yes | |
| AggStep | Yes | |
| AggStep | Yes | |
| And | Yes | |
| AutoCommit | No | |
| BitAnd | Yes | |
| BitNot | Yes | |
| BitOr | Yes | |
| Blob | Yes | |
| Checkpoint | No | |
| Clear | No | |
| Close | No | |
| CollSeq | No | |
| Column | Yes | |
| Compare | Yes | |
| Concat | Yes | |
| Copy | Yes | |
| Count | No | |
| CreateBTree | Partial| no temp databases |
| CreateTable | No | |
| CreateTable | No | |
| DecrJumpZero | Yes | |
| Delete | No | |
| Destroy | No | |
| Divide | Yes | |
| DropIndex | No | |
| DropTable | No | |
| DropTrigger | No | |
| EndCoroutine | Yes | |
| Eq | Yes | |
| Expire | No | |
| Explain | No | |
| FkCounter | No | |
| FkIfZero | No | |
| Found | No | |
| Function | Yes | |
| Ge | Yes | |
| Gosub | Yes | |
| Goto | Yes | |
| Gt | Yes | |
| Halt | Yes | |
| HaltIfNull | No | |
| IdxDelete | No | |
| IdxGE | Yes | |
| IdxInsert | No | |
| IdxLT | No | |
| IdxRowid | No | |
| If | Yes | |
| IfNeg | No | |
| IfNot | Yes | |
| IfPos | Yes | |
| IfZero | No | |
| IncrVacuum | No | |
| Init | Yes | |
| InitCoroutine | Yes | |
| Insert | No | |
| InsertAsync | Yes | |
| InsertAwait | Yes | |
| InsertInt | No | |
| Int64 | No | |
| Integer | Yes | |
| IntegrityCk | No | |
| IsNull | Yes | |
| IsUnique | No | |
| JournalMode | No | |
| Jump | Yes | |
| Last | No | |
| Le | Yes | |
| LoadAnalysis | No | |
| Lt | Yes | |
| MakeRecord | Yes | |
| MaxPgcnt | No | |
| MemMax | No | |
| Move | No | |
| Multiply | Yes | |
| MustBeInt | Yes | |
| Ne | Yes | |
| NewRowid | Yes | |
| Next | No | |
| NextAsync | Yes | |
| NextAwait | Yes | |
| Noop | Yes | |
| Not | Yes | |
| NotExists | Yes | |
| NotFound | No | |
| NotNull | Yes | |
| Null | Yes | |
| NullRow | Yes | |
| Once | No | |
| OpenAutoindex | No | |
| OpenEphemeral | No | |
| OpenPseudo | Yes | |
| OpenRead | Yes | |
| OpenReadAsync | Yes | |
| OpenWrite | No | |
| OpenWriteAsync | Yes | |
| OpenWriteAwait | Yes | |
| Or | Yes | |
| Pagecount | Partial| no temp databases |
| Param | No | |
| ParseSchema | No | |
| Permutation | No | |
| Prev | No | |
| PrevAsync | Yes | |
| PrevAwait | Yes | |
| Program | No | |
| ReadCookie | No | |
| Real | Yes | |
| RealAffinity | Yes | |
| Remainder | Yes | |
| ResetCount | No | |
| ResultRow | Yes | |
| Return | Yes | |
| Rewind | Yes | |
| RewindAsync | Yes | |
| RewindAwait | Yes | |
| RowData | No | |
| RowId | Yes | |
| RowKey | No | |
| RowSetAdd | No | |
| RowSetRead | No | |
| RowSetTest | No | |
| Rowid | Yes | |
| SCopy | No | |
| Savepoint | No | |
| Seek | No | |
| SeekGe | Yes | |
| SeekGt | Yes | |
| SeekLe | No | |
| SeekLt | No | |
| SeekRowid | Yes | |
| Sequence | No | |
| SetCookie | No | |
| ShiftLeft | Yes | |
| ShiftRight | Yes | |
| SoftNull | Yes | |
| Sort | No | |
| SorterCompare | No | |
| SorterData | Yes | |
| SorterInsert | Yes | |
| SorterNext | Yes | |
| SorterOpen | Yes | |
| SorterSort | Yes | |
| String | No | |
| String8 | Yes | |
| Subtract | Yes | |
| TableLock | No | |
| ToBlob | No | |
| ToInt | No | |
| ToNumeric | No | |
| ToReal | No | |
| ToText | No | |
| Trace | No | |
| Transaction | Yes | |
| VBegin | No | |
| VColumn | No | |
| VCreate | No | |
| VDestroy | No | |
| VFilter | No | |
| VNext | No | |
| VOpen | No | |
| VRename | No | |
| VUpdate | No | |
| Vacuum | No | |
| Variable | No | |
| VerifyCookie | No | |
| Yield | Yes | |
| ZeroOrNull | Yes | |
## [SQLite journaling modes](https://www.sqlite.org/pragma.html#pragma_journal_mode)
We currently don't have plan to support the rollback journal mode as it locks the database file during writes.
Therefore, all rollback-type modes (delete, truncate, persist, memory) are marked are `Not Needed` below.
| Journal mode | Status | Comment |
|--------------|------------|--------------------------------|
| wal | Yes | |
| wal2 | No | experimental feature in sqlite |
| delete | Not Needed | |
| truncate | Not Needed | |
| persist | Not Needed | |
| memory | Not Needed | |
## Extensions
Limbo has in-tree extensions.
### UUID
UUID's in Limbo are `blobs` by default.
| Function | Status | Comment |
|-----------------------|--------|---------------------------------------------------------------|
| uuid4() | Yes | UUID version 4 |
| uuid4_str() | Yes | UUID v4 string alias `gen_random_uuid()` for PG compatibility |
| uuid7(X?) | Yes | UUID version 7 (optional parameter for seconds since epoch) |
| uuid7_timestamp_ms(X) | Yes | Convert a UUID v7 to milliseconds since epoch |
| uuid_str(X) | Yes | Convert a valid UUID to string |
| uuid_blob(X) | Yes | Convert a valid UUID to blob |
### regexp
The `regexp` extension is compatible with [sqlean-regexp](https://github.com/nalgeon/sqlean/blob/main/docs/regexp.md).
| Function | Status | Comment |
|------------------------------------------------|--------|---------|
| regexp(pattern, source) | Yes | |
| regexp_like(source, pattern) | Yes | |
| regexp_substr(source, pattern) | Yes | |
| regexp_capture(source, pattern[, n]) | No | |
| regexp_replace(source, pattern, replacement) | No | |
### Vector
The `vector` extension is compatible with libSQL native vector search.
| Function | Status | Comment |
|------------------------------------------------|--------|---------|
| vector(x) | Yes | |
| vector32(x) | Yes | |
| vector64(x) | Yes | |
| vector_extract(x) | Yes | |
| vector_distance_cos(x, y) | Yes | |
Reference in New Issue View Git Blame Copy Permalink