Documentation
¶
Overview ¶
Package slowquery parses Postgres and MySQL slow-query log lines into structured entries with a timestamp, duration, and query text.
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Entry ¶
type Entry struct {
Timestamp time.Time
// DurationMs is the statement's own reported execution time in
// milliseconds (Postgres' "duration:", MySQL's "Query_time"
// converted from seconds).
DurationMs float64
Query string
// RowsExamined is 0 when the engine's slow query log doesn't report
// it (Postgres never does; MySQL always does for a real slow-log
// entry).
RowsExamined int64
}
Entry is one parsed slow query.
func ParseMySQL ¶
ParseMySQL extracts every slow-query entry from lines, in the order given, reconstructing each entry's multi-line block: a "# Query_time:" header, an optional "# User@Host:"/"SET timestamp=...;" line, then one or more lines of SQL text terminated by the next header line (another "#"-prefixed line) or the end of input. Everything before the first header line, and any "#"-prefixed line that isn't a header this package recognizes (e.g. "# Time:", "# User@Host:"), is skipped.
Example ¶
package main
import (
"fmt"
"time"
"github.com/GLINCKER/levelrail/kit/slowquery"
)
func main() {
now := time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC)
lines := []slowquery.LogLine{
{Timestamp: now, Message: "# Query_time: 2.500000 Lock_time: 0.000100 Rows_sent: 1 Rows_examined: 90000"},
{Timestamp: now, Message: "SELECT COUNT(*) FROM events;"},
}
for _, e := range slowquery.ParseMySQL(lines) {
fmt.Printf("%.0f ms, %d rows examined: %s\n", e.DurationMs, e.RowsExamined, e.Query)
}
}
Output: 2500 ms, 90000 rows examined: SELECT COUNT(*) FROM events
func ParsePostgres ¶
ParsePostgres extracts every slow-statement entry from lines, in the order given. Non-matching lines (ordinary Postgres log output that isn't a duration line) are skipped, not treated as an error: the raw log stream mixes slow-query lines with every other message Postgres writes to stderr.
Example ¶
package main
import (
"fmt"
"time"
"github.com/GLINCKER/levelrail/kit/slowquery"
)
func main() {
now := time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC)
lines := []slowquery.LogLine{
{Timestamp: now, Message: "2026-01-01 00:00:00 UTC [41] LOG: checkpoint starting: time"},
{Timestamp: now, Message: "2026-01-01 00:00:01 UTC [42] LOG: duration: 1532.411 ms statement: SELECT * FROM orders WHERE status = 'open'"},
}
for _, e := range slowquery.ParsePostgres(lines) {
fmt.Printf("%.0f ms: %s\n", e.DurationMs, e.Query)
}
}
Output: 1532 ms: SELECT * FROM orders WHERE status = 'open'
Source Files