Documentation
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Overview ¶
Package crossverify checks that a database an engine loaded from a generated SQL script holds what the SQLite source holds: the same tables, columns, keys, indexes and every value.
It is an internal package on purpose. It is the verifier of the CI journey of `datatug db copy --to sqlscript:` (scripts/check-journey-mysql.sh), not a command: its long-term home is an extension of `datatug compare` once compare's known defects are fixed, and until then no second public comparison command exists.
The target is read through its Go driver, never through text conversions in the engine: integers as int64, floats as the 64 bits the engine returns, decimals as exact rationals, blobs as bytes. Only a date or time is compared as text, in the format the column was created with. The rules for each column kind are in canon.go. The verifier does not use the script writer's literal code, so a bug of the writer cannot hide itself.
What it expects is the plan the exporter makes for the same SQLite file (faithful.PlanScript), not the warnings of the export: a renamed index is expected under its new name, and the indexes an engine creates itself for a foreign key are modelled and left out.
Index ¶
Constants ¶
const ( EngineMySQL = "mysql" EngineMSSQL = "mssql" )
Engine names the engines the verifier knows.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Input ¶
type Input struct {
Plan *faithful.ScriptPlan
Source *sql.DB
Target *sql.DB
// Schema is the MySQL database (the SQL Server schema); the connection's current one when empty.
Schema string
// Engine is the engine that loaded the script: EngineMySQL (the default) or EngineMSSQL.
Engine string
// SourceSHA256 is the hash of the SQLite file, checked against the marker row; "" skips that check.
SourceSHA256 string
// contains filtered or unexported fields
}
Input is what to compare: the plan the exporter makes for the SQLite source, the source, and the database the script was loaded into.
type MyCheck ¶ added in v0.97.1
type MyCheck struct {
Name, Clause string
}
MyCheck is a check constraint: its name and the clause as the server prints it (CHECK_CLAUSE).
type MyColumn ¶
type MyColumn struct {
Name, Type string
Nullable bool
AutoIncrement bool
HasDefault bool
// Default is COLUMN_DEFAULT as the server prints it: the value of a literal default, the text of an
// expression default (Generated).
Default string
Generated bool
}
MyColumn is a column as MySQL reports it.
type MyFK ¶
type MyFK struct {
Name string
Columns []string
RefTable string
RefColumns []string
OnUpdate string
OnDelete string
}
MyFK is a foreign key.
type MyIndex ¶
type MyIndex struct {
Name string
Unique bool
// Filtered is true for an index with a WHERE clause (SQL Server).
Filtered bool
Columns []MyIndexColumn
}
MyIndex is an index (a unique constraint is a unique index in MySQL).
type MyIndexColumn ¶
type MyIndexColumn struct {
Name string
Desc bool
// Prefix is the indexed prefix length of a prefix index, 0 for the whole column.
Prefix int
}
MyIndexColumn is one key part of an index.
type MySQLCatalog ¶
MySQLCatalog is the catalog of one MySQL database.
func ReadMSSQL ¶ added in v0.99.0
ReadMSSQL reads the catalog of schema (the connection's current schema when empty) from the sys views of SQL Server. The result has the shape of the MySQL catalog: the backing index of the primary key is the primary key, the backing index of a UNIQUE constraint is a unique index of the constraint's name, and a foreign key, check constraint or index that is disabled or filtered is flagged.
func ReadMySQL ¶
ReadMySQL reads the catalog of schema (the current database when empty) from information_schema.
func (*MySQLCatalog) Table ¶
func (c *MySQLCatalog) Table(name string) *MyTable
Table returns the table called name, or nil.
type MyTable ¶
type MyTable struct {
Name string
Columns []MyColumn
PK []string
Indexes []MyIndex // without the primary key
FKs []MyFK
Checks int
// CheckClauses are the check constraints, ordered by name.
CheckClauses []MyCheck
// Untrusted names the constraints the engine reports as disabled or not checked against the rows (SQL Server).
Untrusted []string
}
MyTable is a table as MySQL reports it.
type Queryer ¶
type Queryer interface {
QueryContext(ctx context.Context, query string, args ...any) (*sql.Rows, error)
QueryRowContext(ctx context.Context, query string, args ...any) *sql.Row
}
Queryer is what the reader needs: a *sql.DB, *sql.Conn or *sql.Tx.
type Result ¶
type Result struct {
Diffs []faithful.Diff
Tables int
Rows int64
// Values is the number of values compared one by one.
Values int64
}
Result is what a verification found.
func Verify ¶
Verify compares the plan and the SQLite source with what MySQL holds: tables, columns (type, nullability, auto-increment, default), primary keys, foreign keys, unique keys and indexes (the indexes MySQL creates itself for a foreign key excluded), check constraints, row counts, the completion marker, and every value.
Source Files