Improve statistics backup queries

backup/statistics.go

@@ -69,16 +69,16 @@ func GenerateAttributeStatisticsQueries(table Table, attStat AttributeStatistic)
 		attributeSlotsQueryStr = generateAttributeSlotsQuery4(attStat)
 	}
 
-	attributeQueries = append(attributeQueries, fmt.Sprintf(`DELETE FROM pg_statistic
-WHERE starelid = %s AND staattnum = (SELECT attnum FROM pg_attribute WHERE attrelid = %s AND attname = '%s');`, starelidStr, starelidStr, utils.EscapeSingleQuotes(attStat.AttName)))
+	attributeQueries = append(attributeQueries, fmt.Sprintf(`WITH attr_info AS (SELECT attrelid, attnum FROM pg_attribute WHERE attrelid = %s AND attname = '%s')
+DELETE FROM pg_statistic WHERE starelid = (SELECT attrelid from attr_info) AND staattnum = (SELECT attnum from attr_info);`, starelidStr, utils.EscapeSingleQuotes(attStat.AttName)))
 	attributeQueries = append(attributeQueries, fmt.Sprintf(`INSERT INTO pg_statistic SELECT
-	%s,
+	attrelid,
 	attnum,%s
 	%f::real,
 	%d::integer,
 	%f::real,
 	%s
-FROM pg_attribute WHERE attrelid = %s AND attname = '%s';`, starelidStr, inheritStr, attStat.NullFraction, attStat.Width, attStat.Distinct, attributeSlotsQueryStr, starelidStr, utils.EscapeSingleQuotes(attStat.AttName)))
+FROM pg_attribute WHERE attrelid = %s AND attname = '%s';`, inheritStr, attStat.NullFraction, attStat.Width, attStat.Distinct, attributeSlotsQueryStr, starelidStr, utils.EscapeSingleQuotes(attStat.AttName)))
 
 	/*
 	 * If a type name starts with exactly one underscore, it describes an array

backup/statistics_test.go

@@ -100,11 +100,10 @@ SET
 	reltuples = 0.000000::real
 WHERE oid = 'testschema.testtable2'::regclass::oid;`,
 
-				`DELETE FROM pg_statistic
-WHERE starelid = 'testschema.testtable2'::regclass::oid AND staattnum = (SELECT attnum FROM pg_attribute WHERE attrelid = 'testschema.testtable2'::regclass::oid AND attname = 'testattWithArray');`,
-
+				`WITH attr_info AS (SELECT attrelid, attnum FROM pg_attribute WHERE attrelid = 'testschema.testtable2'::regclass::oid AND attname = 'testattWithArray')
+DELETE FROM pg_statistic WHERE starelid = (SELECT attrelid from attr_info) AND staattnum = (SELECT attnum from attr_info);`,
 				fmt.Sprintf(`INSERT INTO pg_statistic SELECT
-	'testschema.testtable2'::regclass::oid,
+	attrelid,
 	attnum,%[1]s
 	0.000000::real,
 	0::integer,
@@ -127,11 +126,10 @@ WHERE starelid = 'testschema.testtable2'::regclass::oid AND staattnum = (SELECT
 	NULL
 FROM pg_attribute WHERE attrelid = 'testschema.testtable2'::regclass::oid AND attname = 'testattWithArray';`, insertReplace1, insertReplace2, insertReplace3, insertReplace4, insertReplace5),
 
-				`DELETE FROM pg_statistic
-WHERE starelid = 'testschema.testtable2'::regclass::oid AND staattnum = (SELECT attnum FROM pg_attribute WHERE attrelid = 'testschema.testtable2'::regclass::oid AND attname = 'testatt');`,
-
+				`WITH attr_info AS (SELECT attrelid, attnum FROM pg_attribute WHERE attrelid = 'testschema.testtable2'::regclass::oid AND attname = 'testatt')
+DELETE FROM pg_statistic WHERE starelid = (SELECT attrelid from attr_info) AND staattnum = (SELECT attnum from attr_info);`,
 				fmt.Sprintf(`INSERT INTO pg_statistic SELECT
-	'testschema.testtable2'::regclass::oid,
+	attrelid,
 	attnum,%[1]s
 	0.400000::real,
 	10::integer,
@@ -183,12 +181,12 @@ WHERE oid = '"""test''schema"""."""test''table"""'::regclass::oid;`))
 			}
 
 			attStatsQueries := backup.GenerateAttributeStatisticsQueries(tableTestTable, attStats)
-			Expect(attStatsQueries[0]).To(Equal(fmt.Sprintf(`DELETE FROM pg_statistic
-WHERE starelid = 'testschema."test''table"'::regclass::oid AND staattnum = (SELECT attnum FROM pg_attribute WHERE attrelid = 'testschema."test''table"'::regclass::oid AND attname = 'testatt');`)))
+			Expect(attStatsQueries[0]).To(Equal(fmt.Sprintf(`WITH attr_info AS (SELECT attrelid, attnum FROM pg_attribute WHERE attrelid = 'testschema."test''table"'::regclass::oid AND attname = 'testatt')
+DELETE FROM pg_statistic WHERE starelid = (SELECT attrelid from attr_info) AND staattnum = (SELECT attnum from attr_info);`)))
 
 			insertReplace1, insertReplace2, insertReplace3, insertReplace4, insertReplace5 := getStatInsertReplace(0, 0)
 			Expect(attStatsQueries[1]).To(Equal(fmt.Sprintf(`INSERT INTO pg_statistic SELECT
-	'testschema."test''table"'::regclass::oid,
+	attrelid,
 	attnum,%s
 	0.400000::real,
 	10::integer,
@@ -222,12 +220,12 @@ FROM pg_attribute WHERE attrelid = 'testschema."test''table"'::regclass::oid AND
 
 			attStatsQueries := backup.GenerateAttributeStatisticsQueries(tableTestTable, attStats)
 
-			Expect(attStatsQueries[0]).To(Equal(fmt.Sprintf(`DELETE FROM pg_statistic
-WHERE starelid = 'testschema."test''table"'::regclass::oid AND staattnum = (SELECT attnum FROM pg_attribute WHERE attrelid = 'testschema."test''table"'::regclass::oid AND attname = 'testatt');`)))
+			Expect(attStatsQueries[0]).To(Equal(fmt.Sprintf(`WITH attr_info AS (SELECT attrelid, attnum FROM pg_attribute WHERE attrelid = 'testschema."test''table"'::regclass::oid AND attname = 'testatt')
+DELETE FROM pg_statistic WHERE starelid = (SELECT attrelid from attr_info) AND staattnum = (SELECT attnum from attr_info);`)))
 
 			insertReplace1, insertReplace2, insertReplace3, insertReplace4, insertReplace5 := getStatInsertReplace(10, 12)
 			Expect(attStatsQueries[1]).To(Equal(fmt.Sprintf(`INSERT INTO pg_statistic SELECT
-	'testschema."test''table"'::regclass::oid,
+	attrelid,
 	attnum,%s
 	0.400000::real,
 	10::integer,

restore/restore.go

@@ -410,15 +410,14 @@ func editStatementsRedirectSchema(statements []toc.StatementWithType, redirectSc
 		return
 	}
 
-	schemaMatch := `(?:".+?"|[^."']+?)` // matches either an unquoted schema with no dots and no quotes or a quoted schema
+	schemaMatch := `(?:".+?"|[^.]+?)` // matches either an unquoted schema with no dots or a quoted schema containing dots
 	// This expression matches a GRANT or REVOKE statement on any object and captures the old schema name
 	permissionsRE := regexp.MustCompile(fmt.Sprintf(`(?m)(^(?:REVOKE|GRANT) .+ ON .+?) (%s)((\..+)? (?:FROM|TO) .+)`, schemaMatch))
 	// This expression matches an ATTACH PARTITION statement and captures both the parent and child schema names
 	attachRE := regexp.MustCompile(fmt.Sprintf(`(ALTER TABLE(?: ONLY)?) (%[1]s)(\..+ ATTACH PARTITION) (%[1]s)(\..+)`, schemaMatch))
 	// This expression matches a '<schema>.<table>'::regclass::oid expression
 	regclassOidRE := regexp.MustCompile(fmt.Sprintf(`'(%s)((\.[^']+)'\:\:regclass\:\:oid)`, schemaMatch))
-	// These expressions match the first and the last occurences of the '<schema>.<table>'::regclass::oid expression
-	firstRegclassOidRE := regexp.MustCompile(fmt.Sprintf(`(?s)^(.*?)(%s)(.*)$`, regclassOidRE))
+	// These expression matches the last occurence of the '<schema>.<table>'::regclass::oid expression
 	lastRegclassOidRE := regexp.MustCompile(fmt.Sprintf(`(?s)^(.*)(%s)(.*?)$`, regclassOidRE))
 	for i := range statements {
 		oldSchema := fmt.Sprintf("%s.", statements[i].Schema)
@@ -445,10 +444,9 @@ func editStatementsRedirectSchema(statements []toc.StatementWithType, redirectSc
 			replaced = true
 		}
 
-		// Statistic statements need two schema replacements. We replace the first and the last occurences,
-		// to avoid a very small chance that schema name was in the statistic data itself, that we do not want to alter.
+		// Statistic statements needs one schema replacements. We replace the last occurence to avoid a very small
+		// chance that schema name was in the statistic data itself, that we do not want to alter.
 		if strings.Contains(statement, "pg_statistic") {
-			statement = firstRegclassOidRE.ReplaceAllString(statement, fmt.Sprintf("${1}'%s${4}$6", redirectSchema))
 			statement = lastRegclassOidRE.ReplaceAllString(statement, fmt.Sprintf("${1}'%s${4}$6", redirectSchema))
 			replaced = true
 		}