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db

package
v1.1.0 Latest Latest
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 Go to latest Published: Apr 17, 2026 License: Apache-2.0 Imports: 16 Imported by: 0

Documentation

Overview

Package db provides database abstractions and utilities. The main types (Connection, Repository, etc.) are defined in internal/repos/service.go which uses the db.Pool interface for database-agnostic operations.

Index

Constants

This section is empty.

Variables

View Source 
var ErrNoRows = errors.New("no rows in result set")

ErrNoRows is returned when a query returns no results. It wraps different driver-specific errors into a common error.

Functions

func Connect 

func Connect(databaseURL string) (*pgxpool.Pool, error)

Connect creates a new database connection pool (convenience function). DEPRECATED: Use ConnectWithDriver for multi-database support.

func ConvertPlaceholders 

func ConvertPlaceholders(query string, driver DriverType) string

ConvertPlaceholders converts PostgreSQL-style placeholders ($1, $2) to MySQL-style (?) when using MySQL driver.

func IsMySQLDuplicateError 

func IsMySQLDuplicateError(err error) bool

IsMySQLDuplicateError checks if an error is a MySQL duplicate key error.

func IsNoRows 

func IsNoRows(err error) bool

IsNoRows checks if an error is pgx.ErrNoRows.

func IsNoRowsError 

func IsNoRowsError(err error) bool

IsNoRowsError checks if an error is a "no rows" error from any supported driver.

func NormalizeError 

func NormalizeError(err error) error

NormalizeError converts driver-specific errors to common errors.

func PlaceholderStyle 

func PlaceholderStyle(driver DriverType) string

PlaceholderStyle returns the placeholder style for a driver. PostgreSQL uses $1, $2, etc. MySQL uses ?

Types

type DB 

type DB struct {
	// contains filtered or unexported fields
}

DB wraps the database connection pool.

func New 

func New(ctx context.Context, databaseURL string) (*DB, error)

New creates a new database connection.

func (*DB) Close 

func (db *DB) Close()

Close closes the database connection pool.

func (*DB) Pool 

func (db *DB) Pool() *pgxpool.Pool

Pool returns the underlying connection pool.

type DriverType 

type DriverType string

DriverType represents the database driver type. 

const (
	DriverPostgres DriverType = "postgres"
	DriverMySQL    DriverType = "mysql"
)

func DetectDriver 

func DetectDriver(url string) DriverType

DetectDriver detects the database driver from the URL.

type MySQLPool 

type MySQLPool struct {
	// contains filtered or unexported fields
}

MySQLPool wraps sql.DB to implement the Pool interface for MySQL.

func TryGetMySQLPool 

func TryGetMySQLPool(p Pool) (*MySQLPool, bool)

TryGetMySQLPool returns the underlying MySQLPool if available.

func (*MySQLPool) Begin 

func (p *MySQLPool) Begin(ctx context.Context) (Tx, error)

Begin starts a new transaction.

func (*MySQLPool) Close 

func (p *MySQLPool) Close() error

Close closes the connection pool.

func (*MySQLPool) Driver 

func (p *MySQLPool) Driver() DriverType

Driver returns the driver type.

func (*MySQLPool) Exec 

func (p *MySQLPool) Exec(ctx context.Context, sql string, args ...any) (Result, error)

Exec executes a query that doesn't return rows.

func (*MySQLPool) Ping 

func (p *MySQLPool) Ping(ctx context.Context) error

Ping verifies the connection is alive.

func (*MySQLPool) Query 

func (p *MySQLPool) Query(ctx context.Context, sql string, args ...any) (Rows, error)

Query executes a query that returns rows.

func (*MySQLPool) QueryRow 

func (p *MySQLPool) QueryRow(ctx context.Context, sql string, args ...any) Row

QueryRow executes a query that returns at most one row.

func (*MySQLPool) Stats 

func (p *MySQLPool) Stats() PoolStats

Stats returns connection pool statistics.

func (*MySQLPool) Underlying 

func (p *MySQLPool) Underlying() *sql.DB

Underlying returns the underlying sql.DB.

type Pool 

type Pool interface {
	// Query executes a query that returns rows.
	Query(ctx context.Context, sql string, args ...any) (Rows, error)

	// QueryRow executes a query that returns at most one row.
	QueryRow(ctx context.Context, sql string, args ...any) Row

	// Exec executes a query that doesn't return rows.
	Exec(ctx context.Context, sql string, args ...any) (Result, error)

	// Begin starts a new transaction.
	Begin(ctx context.Context) (Tx, error)

	// Ping verifies the connection is alive.
	Ping(ctx context.Context) error

	// Close closes the connection pool.
	Close() error

	// Driver returns the driver type.
	Driver() DriverType

	// Stats returns connection pool statistics.
	Stats() PoolStats
}

Pool is the common interface for database connection pools. It abstracts the differences between pgxpool.Pool and sql.DB.

func ConnectWithDriver 

func ConnectWithDriver(ctx context.Context, databaseURL, driver string) (Pool, error)

ConnectWithDriver creates a new database connection pool with driver detection. The driver is auto-detected from the URL if not specified. Supported drivers: postgres, mysql.

func Open 

func Open(ctx context.Context, url string, cfg PoolConfig) (Pool, error)

Open creates a new database connection pool based on the URL.

type PoolConfig 

type PoolConfig struct {
	MaxOpenConns    int
	MaxIdleConns    int
	ConnMaxLifetime time.Duration
}

PoolConfig contains common pool configuration.

func DefaultPoolConfig 

func DefaultPoolConfig() PoolConfig

DefaultPoolConfig returns default pool configuration.

type PoolStats 

type PoolStats struct {
	MaxOpenConnections int
	OpenConnections    int
	InUse              int
	Idle               int
}

PoolStats contains connection pool statistics.

type PostgresPool 

type PostgresPool struct {
	// contains filtered or unexported fields
}

PostgresPool wraps pgxpool.Pool to implement the Pool interface.

func MustGetPostgresPool 

func MustGetPostgresPool(p Pool) *PostgresPool

MustGetPostgresPool panics if the pool is not a PostgresPool. This is useful for legacy code that requires pgxpool.Pool directly.

func TryGetPostgresPool 

func TryGetPostgresPool(p Pool) (*PostgresPool, bool)

TryGetPostgresPool returns the underlying PostgresPool if available.

func (*PostgresPool) Begin 

func (p *PostgresPool) Begin(ctx context.Context) (Tx, error)

Begin starts a new transaction.

func (*PostgresPool) Close 

func (p *PostgresPool) Close() error

Close closes the connection pool.

func (*PostgresPool) Driver 

func (p *PostgresPool) Driver() DriverType

Driver returns the driver type.

func (*PostgresPool) Exec 

func (p *PostgresPool) Exec(ctx context.Context, sql string, args ...any) (Result, error)

Exec executes a query that doesn't return rows.

func (*PostgresPool) Ping 

func (p *PostgresPool) Ping(ctx context.Context) error

Ping verifies the connection is alive.

func (*PostgresPool) Query 

func (p *PostgresPool) Query(ctx context.Context, sql string, args ...any) (Rows, error)

Query executes a query that returns rows.

func (*PostgresPool) QueryRow 

func (p *PostgresPool) QueryRow(ctx context.Context, sql string, args ...any) Row

QueryRow executes a query that returns at most one row.

func (*PostgresPool) Stats 

func (p *PostgresPool) Stats() PoolStats

Stats returns connection pool statistics.

func (*PostgresPool) Underlying 

func (p *PostgresPool) Underlying() *pgxpool.Pool

Underlying returns the underlying pgxpool.Pool for legacy code.

type Result 

type Result interface {
	RowsAffected() (int64, error)
	LastInsertId() (int64, error)
}

Result is the common interface for exec results.

type Row 

type Row interface {
	Scan(dest ...any) error
}

Row is the common interface for single row results.

type Rows 

type Rows interface {
	Next() bool
	Scan(dest ...any) error
	Close()
	Err() error
}

Rows is the common interface for query results.

type SQLBuilder 

type SQLBuilder struct {
	// contains filtered or unexported fields
}

SQLBuilder helps build database-agnostic SQL queries.

func NewSQLBuilder 

func NewSQLBuilder(driver DriverType) *SQLBuilder

NewSQLBuilder creates a new SQL builder for the given driver.

func (*SQLBuilder) ArrayContains 

func (b *SQLBuilder) ArrayContains(column string, pos int) string

ArrayContains checks if an array contains a value. PostgreSQL: $1 = ANY(column) MySQL: JSON_CONTAINS(column, JSON_QUOTE($1)).

func (*SQLBuilder) ArrayLength 

func (b *SQLBuilder) ArrayLength(column string) string

ArrayLength returns the length of an array. PostgreSQL: cardinality(column) or array_length(column, 1) MySQL: JSON_LENGTH(column).

func (*SQLBuilder) Concat 

func (b *SQLBuilder) Concat(parts ...string) string

Concat returns a string concatenation expression. PostgreSQL: a || b || c MySQL: CONCAT(a, b, c).

func (*SQLBuilder) CountFilter 

func (b *SQLBuilder) CountFilter(condition string) string

CountFilter returns a conditional count expression. PostgreSQL: COUNT(*) FILTER (WHERE condition) MySQL: SUM(CASE WHEN condition THEN 1 ELSE 0 END).

func (*SQLBuilder) ForUpdateSkipLocked 

func (b *SQLBuilder) ForUpdateSkipLocked() string

ForUpdateSkipLocked returns the appropriate locking clause. Both PostgreSQL and MySQL 8.0+ support this syntax.

func (*SQLBuilder) ILike 

func (b *SQLBuilder) ILike(column string) string

ILike returns a case-insensitive LIKE condition. PostgreSQL: column ILIKE pattern MySQL: LOWER(column) LIKE LOWER(pattern).

func (*SQLBuilder) ILikeWithPos 

func (b *SQLBuilder) ILikeWithPos(column string, pos int) string

ILikeArg returns the placeholder for ILIKE condition at given position.

func (*SQLBuilder) LikePattern 

func (b *SQLBuilder) LikePattern(value string) string

LikePattern builds a LIKE pattern with wildcards.

func (*SQLBuilder) Now 

func (b *SQLBuilder) Now() string

Now returns the current timestamp function.

func (*SQLBuilder) Placeholder 

func (b *SQLBuilder) Placeholder(pos int) string

Placeholder returns the placeholder for the given position.

func (*SQLBuilder) Returning 

func (b *SQLBuilder) Returning(columns ...string) string

Returning returns a RETURNING clause or empty string for MySQL.

func (*SQLBuilder) ReturningID 

func (b *SQLBuilder) ReturningID() string

ReturningID returns a RETURNING clause or empty string for MySQL. For MySQL, you need to use LastInsertId() instead.

func (*SQLBuilder) TimestampLiteral 

func (b *SQLBuilder) TimestampLiteral(ts string) string

TimestampLiteral converts a timestamp string to database-specific format. PostgreSQL: '1970-01-01'::timestamptz MySQL: '1970-01-01' (implicit conversion).

func (*SQLBuilder) UpsertQuery 

func (b *SQLBuilder) UpsertQuery(
	table string,
	columns []string,
	conflictKey string,
	updateColumns []string,
) string

UpsertQuery builds an upsert query. PostgreSQL: INSERT ... ON CONFLICT (key) DO UPDATE SET ... MySQL: INSERT ... ON DUPLICATE KEY UPDATE ...

type StringArray 

type StringArray []string

StringArray is a database-agnostic string array type. For PostgreSQL, it uses native TEXT[] type. For MySQL, it serializes to JSON.

func (*StringArray) Scan 

func (a *StringArray) Scan(src any) error

Scan implements the sql.Scanner interface.

func (StringArray) Value 

func (a StringArray) Value() (driver.Value, error)

Value implements the driver.Valuer interface.

type Tx 

type Tx interface {
	// Query executes a query that returns rows.
	Query(ctx context.Context, sql string, args ...any) (Rows, error)

	// QueryRow executes a query that returns at most one row.
	QueryRow(ctx context.Context, sql string, args ...any) Row

	// Exec executes a query that doesn't return rows.
	Exec(ctx context.Context, sql string, args ...any) (Result, error)

	// Commit commits the transaction.
	Commit(ctx context.Context) error

	// Rollback aborts the transaction.
	Rollback(ctx context.Context) error
}

Tx is the common interface for database transactions.

type UnsupportedDriverError 

type UnsupportedDriverError struct {
	Driver string
}

UnsupportedDriverError is returned when an unsupported database driver is specified.

func (*UnsupportedDriverError) Error 

func (e *UnsupportedDriverError) Error() string

Source Files

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