Documentation
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Overview ¶
Package mysql implements the MySQL dialect driver (Tier 2). This file is the lexer profile: token boundaries only, no SQL understanding. Lexing assumes the default sql_mode — double quotes delimit strings (not ANSI_QUOTES) and backslash escapes are active (not NO_BACKSLASH_ESCAPES).
Index ¶
- Constants
- func BuildCatalog(schema []cache.SchemaFile) (*cache.Catalog, error)
- type Frontend
- func (Frontend) Parse(sql string) (dialect.Tree, error)
- func (f Frontend) ProbeExpr(expr string) error
- func (f Frontend) ProbeGroupBy(clause string) error
- func (f Frontend) ProbeInsertValue(expr string) error
- func (f Frontend) ProbeJoinItem(item string) error
- func (f Frontend) ProbeOrderBy(clause string) error
- func (f Frontend) ProbeOrderByKey(expr string) error
- func (f Frontend) ProbeSetItem(item string) error
- type NativeOracle
- func (o *NativeOracle) Describe(ctx context.Context, sql string) (dialect.Desc, error)
- func (o *NativeOracle) Plan(ctx context.Context, sql string) error
- func (o *NativeOracle) ServerVersion(context.Context) (string, error)
- func (o *NativeOracle) Snapshot(ctx context.Context) (*cache.Catalog, error)
- type Oracle
- func (o *Oracle) Describe(ctx context.Context, sql string) (dialect.Desc, error)
- func (o *Oracle) Plan(ctx context.Context, sql string) error
- func (o *Oracle) PlanText(ctx context.Context, sql string) (string, error)
- func (o *Oracle) ServerVersion(ctx context.Context) (string, error)
- func (o *Oracle) Snapshot(ctx context.Context) (*cache.Catalog, error)
- type Profile
- type TypeMap
- type UnsupportedDDLError
Constants ¶
const ( // FlagUnsigned marks UNSIGNED integer/decimal columns. FlagUnsigned uint32 = 1 << 8 // FlagBinary marks binary-charset string/blob columns ([]byte, not // string). FlagBinary uint32 = 1 << 9 )
MySQL has no OIDs; dialect.TypeRef.OID carries the wire-protocol type code (MYSQL_TYPE_*) plus the two flag bits below. The encoding is stable — it is what the committed cache stores.
const CatalogSchemaName = "sqletch"
CatalogSchemaName is the schema name stamped on natively-built catalogs. It matches the devdb container database (devdb/mysql.go's WithDatabase), which is what every server-captured cache and corpus case records — byte-identity across oracle backends (design 15 §3) depends on the two never diverging.
Variables ¶
This section is empty.
Functions ¶
func BuildCatalog ¶
func BuildCatalog(schema []cache.SchemaFile) (*cache.Catalog, error)
BuildCatalog parses the ordered schema inputs into a catalog byte-identical to Snapshot over a server that ran the same DDL: table OIDs 1-based in table-name order, column att numbers are definition ordinals, type names are information_schema COLUMN_TYPE spellings, HasDefault mirrors the snapshot query's predicate (non-NULL default, auto_increment, or generated default).
v1 subset: CREATE TABLE, DROP TABLE, and no-op SET statements.
Types ¶
type Frontend ¶
type Frontend struct{}
Frontend is the TiDB-parser-backed grammar frontend for MySQL.
Unlike pg_query, the TiDB AST carries byte offsets on expression nodes but NOT on relation nodes (TableName/TableSource). Relation locations are recovered lexically: in MySQL a relation name in FROM position is always preceded by FROM/JOIN/','/'('/'.'/INTO/UPDATE, so a monotonic token scan that skips subqueries pins each relation to its name token. See locateRelations.
func (Frontend) ProbeExpr ¶
ProbeExpr checks that expr forms exactly one boolean-position expression: it must parse when parenthesized as a WHERE condition and contribute nothing beyond it. Parenthesis balance is the rules' (lexer-level) concern.
func (Frontend) ProbeGroupBy ¶
ProbeGroupBy checks that clause is exactly one statement-level GROUP BY clause and nothing more.
func (Frontend) ProbeInsertValue ¶
ProbeInsertValue checks that expr is exactly one VALUES row item (including the DEFAULT keyword, which is only legal there).
func (Frontend) ProbeJoinItem ¶
ProbeJoinItem checks that item is a join item attachable to a preceding FROM entry.
func (Frontend) ProbeOrderBy ¶
ProbeOrderBy checks that clause is exactly one statement-level ORDER BY clause and nothing more.
func (Frontend) ProbeOrderByKey ¶
ProbeOrderByKey checks that expr is exactly one sort key.
func (Frontend) ProbeSetItem ¶
ProbeSetItem checks that item is exactly one UPDATE SET assignment.
type NativeOracle ¶
type NativeOracle struct {
// contains filtered or unexported fields
}
NativeOracle is the native-inference oracle backend (design 15): Describe answered by sqletch's own name resolution over a DDL-built catalog plus the Tier 2 annotations, with no server anywhere. It is strict and fail-closed — anything outside the modeled subset is a NativeUnsupportedError (SQLETCH214), never a guess — and its answers must be byte-identical to the server backend's for every input it accepts (the corpus gate pins this).
v1 subset: single top-level SELECT/INSERT/UPDATE/DELETE statements over catalog tables. No derived tables and no subqueries (except the dialect's own arity-0 @in emission); expression result columns need an AS alias and a `-- @column` annotation (D3/D4); ENUM/SET result columns are refused (their wire form differs from their catalog form).
func NewNativeOracle ¶
func NewNativeOracle(schema []cache.SchemaFile, serverVersion string) (*NativeOracle, error)
NewNativeOracle builds the backend from the ordered schema inputs and the pinned server version (which it reports verbatim — under a native backend the pin IS the modeled engine).
func (*NativeOracle) Plan ¶
func (o *NativeOracle) Plan(ctx context.Context, sql string) error
Plan validates like Describe and claims nothing more: there is no planner here (design 15 D2). check --exhaustive under the native backend prints that EXPLAIN coverage needs a server-backed run.
func (*NativeOracle) ServerVersion ¶
func (o *NativeOracle) ServerVersion(context.Context) (string, error)
type Oracle ¶
type Oracle struct {
// contains filtered or unexported fields
}
Oracle is the COM_STMT_PREPARE-backed type oracle. Preparing never executes; result-column metadata (name, type, source table/column) is reliable, while parameter metadata is not typed by the protocol — Desc.Params entries stay zero and the pipeline fills them from the mandatory `-- @param` annotations.
Plan prepares `EXPLAIN <sql>` and executes it with every parameter bound to NULL: executing an EXPLAIN plans the statement without touching data, which surfaces optimizer-stage errors that a bare prepare cannot see.
func (*Oracle) PlanText ¶
PlanText returns the EXPLAIN FORMAT=TREE output for explain --analyze, parameters bound to NULL.
func (*Oracle) Snapshot ¶
Snapshot dumps the current database's columns. MySQL has no OIDs; tables get stable synthetic ones (1-based in table-name order, the query's ORDER BY), and column att numbers are ordinal positions.
The ORDER BY sorts table_name as BINARY (raw byte order) rather than under information_schema's default case-insensitive collation. That makes the synthetic OID assignment byte-identical to the native catalog builder (internal/dialect/mysql/nativecatalog.go), which orders names with Go's sort.Strings — a byte-wise comparison. Under the collation default the two backends assigned different OIDs to mixed-case schemas (e.g. "Zebra" vs "apple": collation → apple, Zebra; bytes → Zebra, apple), silently violating the hard byte-identity-across-backends invariant (design 15 §3). BINARY is used instead of a COLLATE clause because table_name may be utf8mb3 on some servers, for which a utf8mb4 collation name is rejected.
type Profile ¶
type Profile struct{}
func (Profile) CaseInsensitiveIdents ¶
CaseInsensitiveIdents reports that MySQL resolves aliases and column references case-insensitively, so R3/R2 name matching must fold.
func (Profile) InEmptySQL ¶
InEmptySQL is the arity-0 @in emission (FALSE even for NULL operands; MySQL needs FROM DUAL to attach a WHERE).
func (Profile) PlaceholderStyle ¶
func (Profile) PlaceholderStyle() dialect.PlaceholderStyle
PlaceholderStyle declares MySQL's '?' per-occurrence binding.
type TypeMap ¶
type TypeMap struct{}
TypeMap maps encoded MySQL type refs to Go types for generated code. Deliberately conservative: unmapped types are a compile error with the type name in the message — never a silent guess.
type UnsupportedDDLError ¶
type UnsupportedDDLError struct {
File string // schema input path as given
Pos int // byte offset of the offending statement in that file
Msg string
}
UnsupportedDDLError reports a schema statement outside the native catalog builder's modeled subset (design 15 §5.1, decision D5). The CLI maps it to SQLETCH215 with a span into the schema file. Fail closed: anything the builder does not fully model is refused, never approximated.
func (*UnsupportedDDLError) Error ¶
func (e *UnsupportedDDLError) Error() string
Source Files