sql: hide number of placeholder

Previously, placeholder values were kept as is
for fingerprint creation, meaning `IN ($1, $2)`
would be a different fingerprint than `IN ($2, $1)`
even though they should be the same.
This commit replace all placeholder values with `$1`, so we
can still know it was a placeholder, but we don't care about the
number of the placeholder itself.
This is the simplest solution to solve this problem. Other
options (e.g. replace with `$_` or `p_`) were considered but
ultimately they would require other modification on the parser code
to accept these values.

Previously:
`SELECT * FROM t WHERE v IN ($1, $2)` -> `SELECT * FROM t WHERE v IN ($1, $2)`
`SELECT * FROM t WHERE v IN ($2, $1)` -> `SELECT * FROM t WHERE v IN ($2, $1)`

Now:
`SELECT * FROM t WHERE v IN ($1, $2)` -> `SELECT * FROM t WHERE v IN ($1, $1)`
`SELECT * FROM t WHERE v IN ($2, $1)` -> `SELECT * FROM t WHERE v IN ($1, $1)`

Fixes #88074

Release note (sql change): The index of a placeholder
is now replaced to always be `$1` to limit fingerprint creations.

pkg/sql/parser/testdata/backup_restore

@@ -67,7 +67,7 @@ BACKUP TABLE foo INTO $1 IN $2
 ----
 BACKUP TABLE foo INTO $1 IN $2
 BACKUP TABLE (foo) INTO ($1) IN ($2) -- fully parenthesized
-BACKUP TABLE foo INTO $1 IN $2 -- literals removed
+BACKUP TABLE foo INTO $1 IN $1 -- literals removed
 BACKUP TABLE _ INTO $1 IN $2 -- identifiers removed
 
 parse
@@ -171,7 +171,7 @@ SHOW BACKUP FROM $1 IN $2 WITH foo = 'bar'
 ----
 SHOW BACKUP FROM $1 IN $2 WITH foo = 'bar'
 SHOW BACKUP FROM ($1) IN ($2) WITH foo = ('bar') -- fully parenthesized
-SHOW BACKUP FROM $1 IN $2 WITH foo = '_' -- literals removed
+SHOW BACKUP FROM $1 IN $1 WITH foo = '_' -- literals removed
 SHOW BACKUP FROM $1 IN $2 WITH _ = 'bar' -- identifiers removed
 
 parse
@@ -203,7 +203,7 @@ SHOW BACKUP $1 IN $2 WITH foo = 'bar'
 ----
 SHOW BACKUP $1 IN $2 WITH foo = 'bar'
 SHOW BACKUP ($1) IN ($2) WITH foo = ('bar') -- fully parenthesized
-SHOW BACKUP $1 IN $2 WITH foo = '_' -- literals removed
+SHOW BACKUP $1 IN $1 WITH foo = '_' -- literals removed
 SHOW BACKUP $1 IN $2 WITH _ = 'bar' -- identifiers removed
 
 parse
@@ -227,15 +227,15 @@ BACKUP TABLE foo TO $1 INCREMENTAL FROM 'bar', $2, 'baz'
 ----
 BACKUP TABLE foo TO $1 INCREMENTAL FROM 'bar', $2, 'baz'
 BACKUP TABLE (foo) TO ($1) INCREMENTAL FROM ('bar'), ($2), ('baz') -- fully parenthesized
-BACKUP TABLE foo TO $1 INCREMENTAL FROM '_', $2, '_' -- literals removed
+BACKUP TABLE foo TO $1 INCREMENTAL FROM '_', $1, '_' -- literals removed
 BACKUP TABLE _ TO $1 INCREMENTAL FROM 'bar', $2, 'baz' -- identifiers removed
 
 parse
 BACKUP foo TO $1 INCREMENTAL FROM 'bar', $2, 'baz'
 ----
 BACKUP TABLE foo TO $1 INCREMENTAL FROM 'bar', $2, 'baz' -- normalized!
 BACKUP TABLE (foo) TO ($1) INCREMENTAL FROM ('bar'), ($2), ('baz') -- fully parenthesized
-BACKUP TABLE foo TO $1 INCREMENTAL FROM '_', $2, '_' -- literals removed
+BACKUP TABLE foo TO $1 INCREMENTAL FROM '_', $1, '_' -- literals removed
 BACKUP TABLE _ TO $1 INCREMENTAL FROM 'bar', $2, 'baz' -- identifiers removed
 
 parse
@@ -301,15 +301,15 @@ BACKUP DATABASE foo TO ($1, $2)
 ----
 BACKUP DATABASE foo TO ($1, $2)
 BACKUP DATABASE foo TO (($1), ($2)) -- fully parenthesized
-BACKUP DATABASE foo TO ($1, $2) -- literals removed
+BACKUP DATABASE foo TO ($1, $1) -- literals removed
 BACKUP DATABASE _ TO ($1, $2) -- identifiers removed
 
 parse
 BACKUP DATABASE foo TO ($1, $2) INCREMENTAL FROM 'baz'
 ----
 BACKUP DATABASE foo TO ($1, $2) INCREMENTAL FROM 'baz'
 BACKUP DATABASE foo TO (($1), ($2)) INCREMENTAL FROM ('baz') -- fully parenthesized
-BACKUP DATABASE foo TO ($1, $2) INCREMENTAL FROM '_' -- literals removed
+BACKUP DATABASE foo TO ($1, $1) INCREMENTAL FROM '_' -- literals removed
 BACKUP DATABASE _ TO ($1, $2) INCREMENTAL FROM 'baz' -- identifiers removed
 
 parse
@@ -400,39 +400,39 @@ RESTORE TABLE foo FROM $2 IN $1
 ----
 RESTORE TABLE foo FROM $2 IN $1
 RESTORE TABLE (foo) FROM ($2) IN ($1) -- fully parenthesized
-RESTORE TABLE foo FROM $2 IN $1 -- literals removed
+RESTORE TABLE foo FROM $1 IN $1 -- literals removed
 RESTORE TABLE _ FROM $2 IN $1 -- identifiers removed
 
 parse
 RESTORE TABLE foo FROM $1, $2, 'bar'
 ----
 RESTORE TABLE foo FROM $1, $2, 'bar'
 RESTORE TABLE (foo) FROM ($1), ($2), ('bar') -- fully parenthesized
-RESTORE TABLE foo FROM $1, $2, '_' -- literals removed
+RESTORE TABLE foo FROM $1, $1, '_' -- literals removed
 RESTORE TABLE _ FROM $1, $2, 'bar' -- identifiers removed
 
 parse
 RESTORE foo FROM $1, $2, 'bar'
 ----
 RESTORE TABLE foo FROM $1, $2, 'bar' -- normalized!
 RESTORE TABLE (foo) FROM ($1), ($2), ('bar') -- fully parenthesized
-RESTORE TABLE foo FROM $1, $2, '_' -- literals removed
+RESTORE TABLE foo FROM $1, $1, '_' -- literals removed
 RESTORE TABLE _ FROM $1, $2, 'bar' -- identifiers removed
 
 parse
 RESTORE TABLE foo FROM 'abc' IN $1, $2, 'bar'
 ----
 RESTORE TABLE foo FROM 'abc' IN $1, $2, 'bar'
 RESTORE TABLE (foo) FROM ('abc') IN ($1), ($2), ('bar') -- fully parenthesized
-RESTORE TABLE foo FROM '_' IN $1, $2, '_' -- literals removed
+RESTORE TABLE foo FROM '_' IN $1, $1, '_' -- literals removed
 RESTORE TABLE _ FROM 'abc' IN $1, $2, 'bar' -- identifiers removed
 
 parse
 RESTORE TABLE foo FROM $4 IN $1, $2, 'bar'
 ----
 RESTORE TABLE foo FROM $4 IN $1, $2, 'bar'
 RESTORE TABLE (foo) FROM ($4) IN ($1), ($2), ('bar') -- fully parenthesized
-RESTORE TABLE foo FROM $4 IN $1, $2, '_' -- literals removed
+RESTORE TABLE foo FROM $1 IN $1, $1, '_' -- literals removed
 RESTORE TABLE _ FROM $4 IN $1, $2, 'bar' -- identifiers removed
 
 parse
@@ -539,119 +539,119 @@ RESTORE DATABASE foo FROM ($1, $2)
 ----
 RESTORE DATABASE foo FROM ($1, $2)
 RESTORE DATABASE foo FROM (($1), ($2)) -- fully parenthesized
-RESTORE DATABASE foo FROM ($1, $2) -- literals removed
+RESTORE DATABASE foo FROM ($1, $1) -- literals removed
 RESTORE DATABASE _ FROM ($1, $2) -- identifiers removed
 
 parse
 RESTORE DATABASE foo FROM ($1), ($2)
 ----
 RESTORE DATABASE foo FROM $1, $2 -- normalized!
 RESTORE DATABASE foo FROM ($1), ($2) -- fully parenthesized
-RESTORE DATABASE foo FROM $1, $2 -- literals removed
+RESTORE DATABASE foo FROM $1, $1 -- literals removed
 RESTORE DATABASE _ FROM $1, $2 -- identifiers removed
 
 parse
 RESTORE DATABASE foo FROM ($1), ($2, $3)
 ----
 RESTORE DATABASE foo FROM $1, ($2, $3) -- normalized!
 RESTORE DATABASE foo FROM ($1), (($2), ($3)) -- fully parenthesized
-RESTORE DATABASE foo FROM $1, ($2, $3) -- literals removed
+RESTORE DATABASE foo FROM $1, ($1, $1) -- literals removed
 RESTORE DATABASE _ FROM $1, ($2, $3) -- identifiers removed
 
 parse
 RESTORE DATABASE foo FROM ($1, $2), $3
 ----
 RESTORE DATABASE foo FROM ($1, $2), $3
 RESTORE DATABASE foo FROM (($1), ($2)), ($3) -- fully parenthesized
-RESTORE DATABASE foo FROM ($1, $2), $3 -- literals removed
+RESTORE DATABASE foo FROM ($1, $1), $1 -- literals removed
 RESTORE DATABASE _ FROM ($1, $2), $3 -- identifiers removed
 
 parse
 RESTORE DATABASE foo FROM $1, ($2, $3)
 ----
 RESTORE DATABASE foo FROM $1, ($2, $3)
 RESTORE DATABASE foo FROM ($1), (($2), ($3)) -- fully parenthesized
-RESTORE DATABASE foo FROM $1, ($2, $3) -- literals removed
+RESTORE DATABASE foo FROM $1, ($1, $1) -- literals removed
 RESTORE DATABASE _ FROM $1, ($2, $3) -- identifiers removed
 
 parse
 RESTORE DATABASE foo FROM ($1, $2), ($3, $4)
 ----
 RESTORE DATABASE foo FROM ($1, $2), ($3, $4)
 RESTORE DATABASE foo FROM (($1), ($2)), (($3), ($4)) -- fully parenthesized
-RESTORE DATABASE foo FROM ($1, $2), ($3, $4) -- literals removed
+RESTORE DATABASE foo FROM ($1, $1), ($1, $1) -- literals removed
 RESTORE DATABASE _ FROM ($1, $2), ($3, $4) -- identifiers removed
 
 parse
 RESTORE DATABASE foo FROM ($1, $2), ($3, $4) AS OF SYSTEM TIME '1'
 ----
 RESTORE DATABASE foo FROM ($1, $2), ($3, $4) AS OF SYSTEM TIME '1'
 RESTORE DATABASE foo FROM (($1), ($2)), (($3), ($4)) AS OF SYSTEM TIME ('1') -- fully parenthesized
-RESTORE DATABASE foo FROM ($1, $2), ($3, $4) AS OF SYSTEM TIME '_' -- literals removed
+RESTORE DATABASE foo FROM ($1, $1), ($1, $1) AS OF SYSTEM TIME '_' -- literals removed
 RESTORE DATABASE _ FROM ($1, $2), ($3, $4) AS OF SYSTEM TIME '1' -- identifiers removed
 
 parse
 RESTORE FROM ($1, $2)
 ----
 RESTORE FROM ($1, $2)
 RESTORE FROM (($1), ($2)) -- fully parenthesized
-RESTORE FROM ($1, $2) -- literals removed
+RESTORE FROM ($1, $1) -- literals removed
 RESTORE FROM ($1, $2) -- identifiers removed
 
 parse
 RESTORE FROM ($1, $2), $3
 ----
 RESTORE FROM ($1, $2), $3
 RESTORE FROM (($1), ($2)), ($3) -- fully parenthesized
-RESTORE FROM ($1, $2), $3 -- literals removed
+RESTORE FROM ($1, $1), $1 -- literals removed
 RESTORE FROM ($1, $2), $3 -- identifiers removed
 
 parse
 RESTORE FROM $1, ($2, $3)
 ----
 RESTORE FROM $1, ($2, $3)
 RESTORE FROM ($1), (($2), ($3)) -- fully parenthesized
-RESTORE FROM $1, ($2, $3) -- literals removed
+RESTORE FROM $1, ($1, $1) -- literals removed
 RESTORE FROM $1, ($2, $3) -- identifiers removed
 
 parse
 RESTORE FROM ($1, $2), ($3, $4)
 ----
 RESTORE FROM ($1, $2), ($3, $4)
 RESTORE FROM (($1), ($2)), (($3), ($4)) -- fully parenthesized
-RESTORE FROM ($1, $2), ($3, $4) -- literals removed
+RESTORE FROM ($1, $1), ($1, $1) -- literals removed
 RESTORE FROM ($1, $2), ($3, $4) -- identifiers removed
 
 parse
 RESTORE FROM ($1, $2), ($3, $4) AS OF SYSTEM TIME '1'
 ----
 RESTORE FROM ($1, $2), ($3, $4) AS OF SYSTEM TIME '1'
 RESTORE FROM (($1), ($2)), (($3), ($4)) AS OF SYSTEM TIME ('1') -- fully parenthesized
-RESTORE FROM ($1, $2), ($3, $4) AS OF SYSTEM TIME '_' -- literals removed
+RESTORE FROM ($1, $1), ($1, $1) AS OF SYSTEM TIME '_' -- literals removed
 RESTORE FROM ($1, $2), ($3, $4) AS OF SYSTEM TIME '1' -- identifiers removed
 
 parse
 RESTORE FROM $1, $2, 'bar'
 ----
 RESTORE FROM $1, $2, 'bar'
 RESTORE FROM ($1), ($2), ('bar') -- fully parenthesized
-RESTORE FROM $1, $2, '_' -- literals removed
+RESTORE FROM $1, $1, '_' -- literals removed
 RESTORE FROM $1, $2, 'bar' -- identifiers removed
 
 parse
 RESTORE FROM $4 IN $1, $2, 'bar'
 ----
 RESTORE FROM $4 IN $1, $2, 'bar'
 RESTORE FROM ($4) IN ($1), ($2), ('bar') -- fully parenthesized
-RESTORE FROM $4 IN $1, $2, '_' -- literals removed
+RESTORE FROM $1 IN $1, $1, '_' -- literals removed
 RESTORE FROM $4 IN $1, $2, 'bar' -- identifiers removed
 
 parse
 RESTORE FROM $4 IN $1, $2, 'bar' AS OF SYSTEM TIME '1' WITH skip_missing_foreign_keys
 ----
 RESTORE FROM $4 IN $1, $2, 'bar' AS OF SYSTEM TIME '1' WITH skip_missing_foreign_keys
 RESTORE FROM ($4) IN ($1), ($2), ('bar') AS OF SYSTEM TIME ('1') WITH skip_missing_foreign_keys -- fully parenthesized
-RESTORE FROM $4 IN $1, $2, '_' AS OF SYSTEM TIME '_' WITH skip_missing_foreign_keys -- literals removed
+RESTORE FROM $1 IN $1, $1, '_' AS OF SYSTEM TIME '_' WITH skip_missing_foreign_keys -- literals removed
 RESTORE FROM $4 IN $1, $2, 'bar' AS OF SYSTEM TIME '1' WITH skip_missing_foreign_keys -- identifiers removed
 
 parse
@@ -694,15 +694,15 @@ RESTORE TENANT 36 FROM ($1, $2) AS OF SYSTEM TIME '1'
 ----
 RESTORE TENANT 36 FROM ($1, $2) AS OF SYSTEM TIME '1'
 RESTORE TENANT 36 FROM (($1), ($2)) AS OF SYSTEM TIME ('1') -- fully parenthesized
-RESTORE TENANT _ FROM ($1, $2) AS OF SYSTEM TIME '_' -- literals removed
+RESTORE TENANT _ FROM ($1, $1) AS OF SYSTEM TIME '_' -- literals removed
 RESTORE TENANT 36 FROM ($1, $2) AS OF SYSTEM TIME '1' -- identifiers removed
 
 parse
 RESTORE TENANT 36 FROM ($1, $2) WITH tenant = '5'
 ----
 RESTORE TENANT 36 FROM ($1, $2) WITH tenant = '5'
 RESTORE TENANT 36 FROM (($1), ($2)) WITH tenant = ('5') -- fully parenthesized
-RESTORE TENANT _ FROM ($1, $2) WITH tenant = '_' -- literals removed
+RESTORE TENANT _ FROM ($1, $1) WITH tenant = '_' -- literals removed
 RESTORE TENANT 36 FROM ($1, $2) WITH tenant = '5' -- identifiers removed
 
 parse

pkg/sql/parser/testdata/prepared_stmts

@@ -27,7 +27,7 @@ PREPARE a (STRING, STRING) AS SELECT $1, $2
 ----
 PREPARE a (STRING, STRING) AS SELECT $1, $2
 PREPARE a (STRING, STRING) AS SELECT ($1), ($2) -- fully parenthesized
-PREPARE a (STRING, STRING) AS SELECT $1, $2 -- literals removed
+PREPARE a (STRING, STRING) AS SELECT $1, $1 -- literals removed
 PREPARE _ (STRING, STRING) AS SELECT $1, $2 -- identifiers removed
 
 parse
@@ -251,7 +251,7 @@ PREPARE a (STRING, STRING, STRING) AS IMPORT INTO a CSV DATA ($2) WITH temp = $3
 ----
 PREPARE a (STRING, STRING, STRING) AS IMPORT INTO a CSV DATA ($2) WITH temp = $3
 PREPARE a (STRING, STRING, STRING) AS IMPORT INTO a CSV DATA (($2)) WITH temp = ($3) -- fully parenthesized
-PREPARE a (STRING, STRING, STRING) AS IMPORT INTO a CSV DATA ($2) WITH temp = $3 -- literals removed
+PREPARE a (STRING, STRING, STRING) AS IMPORT INTO a CSV DATA ($1) WITH temp = $1 -- literals removed
 PREPARE _ (STRING, STRING, STRING) AS IMPORT INTO _ CSV DATA ($2) WITH _ = $3 -- identifiers removed
 
 parse

pkg/sql/parser/testdata/select_clauses

@@ -195,7 +195,7 @@ SELECT $1, $2 FROM t
 ----
 SELECT $1, $2 FROM t
 SELECT ($1), ($2) FROM t -- fully parenthesized
-SELECT $1, $2 FROM t -- literals removed
+SELECT $1, $1 FROM t -- literals removed
 SELECT $1, $2 FROM _ -- identifiers removed
 
 parse
@@ -2801,7 +2801,7 @@ SELECT a FROM t FETCH FIRST $1 ROWS ONLY OFFSET $2 ROWS
 ----
 SELECT a FROM t LIMIT $1 OFFSET $2 -- normalized!
 SELECT (a) FROM t LIMIT ($1) OFFSET ($2) -- fully parenthesized
-SELECT a FROM t LIMIT $1 OFFSET $2 -- literals removed
+SELECT a FROM t LIMIT $1 OFFSET $1 -- literals removed
 SELECT _ FROM _ LIMIT $1 OFFSET $2 -- identifiers removed
 
 parse

pkg/sql/sem/tree/format_test.go

@@ -479,7 +479,7 @@ func TestFormatNodeSummary(t *testing.T) {
  },
  {
  stmt: `UPDATE system.jobs SET status = $2, payload = $3, last_run = $4, num_runs = $5 WHERE internal_table_id = $1`,
- expected: `UPDATE system.jobs SET status = $2, pa... WHERE internal_table_...`,
+ expected: `UPDATE system.jobs SET status = $1, pa... WHERE internal_table_...`,
  },
  {
  stmt: `UPDATE system.extra_extra_long_table_name SET (schedule_state, next_run) = ($1, $2) WHERE schedule_id = 'name'`,

pkg/sql/sem/tree/hide_constants.go

@@ -34,7 +34,10 @@ func (ctx *FmtCtx) formatNodeOrHideConstants(n NodeFormatter) {
  return
  case *Placeholder:
  // Placeholders should be printed as placeholder markers.
- // Deliberately empty so we format as normal.
+ // Using always '$1' so we limit the amount of different
+ // fingerprints created.
+ ctx.WriteString("$1")
+ return
  case *StrVal:
  ctx.WriteString("'_'")
  return

pkg/sql/sqlstats/sslocal/sql_stats_test.go

@@ -740,12 +740,12 @@ func TestFingerprintCreation(t *testing.T) {
  }()
 
  testConn := sqlutils.MakeSQLRunner(sqlConn)
- testConn.Exec(t, "SET application_name = 'app1'")
  testConn.Exec(t, "CREATE TABLE t (v INT)")
 
  var count int64
 
  t.Run("test hide constants", func(t *testing.T) {
+ testConn.Exec(t, "SET application_name = 'app1'")
  testCases := []struct {
  stmt string
  fingerprint string
@@ -1029,4 +1029,55 @@ func TestFingerprintCreation(t *testing.T) {
  require.Equal(t, tc.count, count)
  }
  })
+
+ t.Run("test hide placeholders", func(t *testing.T) {
+ testConn.Exec(t, "SET application_name = 'app2'")
+ argsOne := []interface{}{1}
+ argsTwo := []interface{}{1, 2}
+ testCases := []struct {
+ stmt string
+ fingerprint string
+ count int64
+ literals []interface{}
+ }{
+ {
+ stmt: "SELECT * FROM t WHERE v IN ($1)",
+ fingerprint: "SELECT * FROM t WHERE v IN ($1,)",
+ count: 1,
+ literals: argsOne,
+ },
+ {
+ stmt: "SELECT * FROM t WHERE v IN (1)",
+ fingerprint: "SELECT * FROM t WHERE v IN (_,)",
+ count: 1,
+ },
+ {
+ stmt: "SELECT * FROM t WHERE v IN ($1, $2)",
+ fingerprint: "SELECT * FROM t WHERE v IN ($1, $1)",
+ count: 1,
+ literals: argsTwo,
+ },
+ {
+ stmt: "SELECT * FROM t WHERE v IN ($2, $1)",
+ fingerprint: "SELECT * FROM t WHERE v IN ($1, $1)",
+ count: 2,
+ literals: argsTwo,
+ },
+ {
+ stmt: "SELECT * FROM t WHERE v IN (1,2)",
+ fingerprint: "SELECT * FROM t WHERE v IN (_, _)",
+ count: 1,
+ },
+ }
+
+ for _, tc := range testCases {
+ testConn.Exec(t, tc.stmt, tc.literals...)
+ rows := testConn.QueryRow(t, "SELECT statistics -> 'statistics' ->> 'cnt' FROM "+
+ "CRDB_INTERNAL.STATEMENT_STATISTICS WHERE app_name = 'app2' "+
+ "AND metadata ->> 'query'=$1", tc.fingerprint)
+ rows.Scan(&count)
+
+ require.Equal(t, tc.count, count)
+ }
+ })
 }