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opt: inline constant values for FK and uniqueness checks
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In FK and uniqueness checks, WithScans that buffer the mutation's input
are replaced with Values expression when inserted values are constant.
This is especially beneficial for `REGIONAL BY ROW` tables where the
`crdb_region` column is a computed column dependent on a FK. Because the
constant values are inlined, the optimizer is not able to reduce a FK
check that scans multiple regions with a FK check that checks only a
single region.

Informs #63882

Release note (performance improvement): Previously, foreign key checks
performed for inserts into `REGIONAL BY ROW` tables always searched the
parent table in all regions to check for FK violations. Now, only a
single region is searched if constant values are inserted and the
`crdb_region` column is a computed column dependent on the FK column.
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@mgartner
mgartner committed May 13, 2021
1 parent 79fe0c7 commit 79293dc
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Showing 21 changed files with 1,091 additions and 808 deletions.
17 changes: 12 additions & 5 deletions pkg/ccl/logictestccl/testdata/logic_test/multi_region_tpcc
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Original file line number Diff line number Diff line change
Expand Up @@ -191,7 +191,8 @@ EXPLAIN INSERT
INTO
history (h_c_id, h_c_d_id, h_c_w_id, h_d_id, h_w_id, h_amount, h_date, h_data)
VALUES
(2057, 4, 3, 4, 3, 2100.9, '2021-04-15 15:22:14', '9 zmssaF9m')
(2057, 4, 3, 4, 3, 2100.9, '2021-04-15 15:22:14', '9 zmssaF9m'),
(2058, 4, 3, 4, 3, 2100.9, '2021-04-15 15:22:14', '9 zmssaF9m')
----
distribution: local
vectorized: true
Expand All @@ -204,8 +205,14 @@ vectorized: true
│ └── • buffer
│ │ label: buffer 1
│ │
│ └── • values
│ size: 11 columns, 1 row
│ └── • render
│ │ estimated row count: 2
│ │
│ └── • render
│ │ estimated row count: 2
│ │
│ └── • values
│ size: 8 columns, 2 rows
│
├── • constraint-check
│ │
Expand All @@ -218,7 +225,7 @@ vectorized: true
│ │ lookup condition: (((column3 = c_w_id) AND (column2 = c_d_id)) AND (column1 = c_id)) AND (crdb_region IN ('ca-central-1', 'us-east-1'))
│ │
│ └── • lookup join (anti)
│ │ estimated row count: 1
│ │ estimated row count: 2
│ │ table: customer@primary
│ │ equality cols are key
│ │ lookup condition: (((column3 = c_w_id) AND (column2 = c_d_id)) AND (column1 = c_id)) AND (crdb_region = 'ap-southeast-2')
Expand All @@ -237,7 +244,7 @@ vectorized: true
│ lookup condition: ((column5 = d_w_id) AND (column4 = d_id)) AND (crdb_region IN ('ca-central-1', 'us-east-1'))
│
└── • lookup join (anti)
│ estimated row count: 1
│ estimated row count: 2
│ table: district@primary
│ equality cols are key
│ lookup condition: ((column5 = d_w_id) AND (column4 = d_id)) AND (crdb_region = 'ap-southeast-2')
Expand Down
124 changes: 51 additions & 73 deletions pkg/ccl/logictestccl/testdata/logic_test/partitioning_implicit
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Original file line number Diff line number Diff line change
Expand Up @@ -238,44 +238,42 @@ vectorized: true
├── • insert
│ │ into: fk_using_implicit_columns_against_t(pk, ref_t_pk, ref_t_c)
│ │
│ └── • buffer
│ │ label: buffer 1
│ │
│ └── • values
│ size: 3 columns, 1 row
│ └── • values
│ size: 3 columns, 1 row
│
├── • constraint-check
│ │
│ └── • error if rows
│ │
│ └── • hash join (right anti)
│ │ equality: (pk) = (column2)
│ │ left cols are key
│ │ right cols are key
│ └── • cross join (anti)
│ │
│ ├── • scan
│ │ missing stats
│ │ table: t@t_b_idx
│ │ spans: FULL SCAN
│ ├── • values
│ │ size: 1 column, 1 row
│ │
│ └── • scan buffer
│ label: buffer 1
│ └── • filter
│ │ filter: pk = 1
│ │
│ └── • scan
│ missing stats
│ table: t@primary
│ spans: [ - /0/1] [/1/1 - /1/1] [/2/1 - ]
│
└── • constraint-check
│
└── • error if rows
│
└── • hash join (right anti)
│ equality: (c) = (column3)
│ right cols are key
└── • cross join (anti)
│
├── • scan
│ missing stats
│ table: t@t_c_key
│ spans: FULL SCAN
├── • values
│ size: 1 column, 1 row
│
└── • scan buffer
label: buffer 1
└── • filter
│ filter: c = 4
│
└── • scan
missing stats
table: t@t_c_key
spans: [ - /2/4] [/3/4 - /3/4] [/4/4 - ]

statement ok
INSERT INTO fk_using_implicit_columns_against_t VALUES (1, 1, 4)
Expand Down Expand Up @@ -701,74 +699,54 @@ vectorized: true
├── • insert
│ │ into: t(pk, pk2, partition_by, a, b, c, d)
│ │
│ └── • buffer
│ │ label: buffer 1
│ │
│ └── • values
│ size: 8 columns, 1 row
│ └── • values
│ size: 8 columns, 1 row
│
├── • constraint-check
│ │
│ └── • error if rows
│ │
│ └── • hash join (right semi)
│ │ equality: (pk) = (column1)
│ │ right cols are key
│ │ pred: column3 != partition_by
│ └── • cross join
│ │
│ ├── • scan
│ │ missing stats
│ │ table: t@t_a_idx
│ │ spans: FULL SCAN
│ ├── • values
│ │ size: 1 column, 1 row
│ │
│ └── • scan buffer
│ label: buffer 1
│ └── • limit
│ │ count: 1
│ │
│ └── • filter
│ │ filter: pk = 1
│ │
│ └── • scan
│ missing stats
│ table: t@t_a_idx
│ spans: [ - /0] [/2 - ]
│
├── • constraint-check
│ │
│ └── • error if rows
│ │
│ └── • hash join (right semi)
│ │ equality: (b) = (column5)
│ │ right cols are key
│ │ pred: (column1 != pk) OR (column3 != partition_by)
│ └── • cross join
│ │
│ ├── • scan
│ │ missing stats
│ │ table: t@t_b_key
│ │ spans: FULL SCAN
│ ├── • values
│ │ size: 1 column, 1 row
│ │
│ └── • scan buffer
│ label: buffer 1
│ └── • limit
│ │ count: 1
│ │
│ └── • filter
│ │ filter: (b = 1) AND ((pk != 1) OR (partition_by != 1))
│ │
│ └── • scan
│ missing stats
│ table: t@t_b_key
│ spans: FULL SCAN
│
└── • constraint-check
│
└── • error if rows
│
└── • limit
│ count: 1
│
└── • lookup join
│ table: t@primary
│ equality: (partition_by, pk) = (partition_by,pk)
│ equality cols are key
│
└── • hash join
│ equality: (c) = (column6)
│ right cols are key
│ pred: (column1 != pk) OR (column3 != partition_by)
│
├── • scan
│ missing stats
│ table: t@t_c_key (partial index)
│ spans: FULL SCAN
│
└── • filter
│ estimated row count: 1
│ filter: column7 > 100
│
└── • scan buffer
label: buffer 1
└── • norows

statement ok
INSERT INTO t VALUES (1, 1, 1, 1, 1, 1, 1), (2, 2, 2, 2, 2, 2, 2)
Expand Down
97 changes: 77 additions & 20 deletions pkg/ccl/logictestccl/testdata/logic_test/regional_by_row
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Original file line number Diff line number Diff line change
Expand Up @@ -930,18 +930,23 @@ SELECT * FROM [EXPLAIN INSERT INTO child VALUES (1, 1)] OFFSET 2
│
└── • error if rows
│
└── • lookup join (anti)
│ table: parent@primary
│ equality cols are key
│ lookup condition: (column2 = p_id) AND (crdb_region IN ('ca-central-1', 'us-east-1'))
└── • cross join (anti)
│
├── • values
│ size: 1 column, 1 row
│
└── • lookup join (anti)
│ table: parent@primary
│ equality cols are key
│ lookup condition: (column2 = p_id) AND (crdb_region = 'ap-southeast-2')
└── • union all
│ limit: 1
│
└── • scan buffer
label: buffer 1
├── • scan
│ missing stats
│ table: parent@primary
│ spans: [/'ap-southeast-2'/1 - /'ap-southeast-2'/1]
│
└── • scan
missing stats
table: parent@primary
spans: [/'ca-central-1'/1 - /'ca-central-1'/1] [/'us-east-1'/1 - /'us-east-1'/1]

query T
SELECT * FROM [EXPLAIN UPSERT INTO child VALUES (1, 1)] OFFSET 2
Expand Down Expand Up @@ -980,18 +985,23 @@ SELECT * FROM [EXPLAIN UPSERT INTO child VALUES (1, 1)] OFFSET 2
│
└── • error if rows
│
└── • lookup join (anti)
│ table: parent@primary
│ equality cols are key
│ lookup condition: (column2 = p_id) AND (crdb_region IN ('ca-central-1', 'us-east-1'))
└── • cross join (anti)
│
├── • values
│ size: 1 column, 1 row
│
└── • lookup join (anti)
│ table: parent@primary
│ equality cols are key
│ lookup condition: (column2 = p_id) AND (crdb_region = 'ap-southeast-2')
└── • union all
│ limit: 1
│
└── • scan buffer
label: buffer 1
├── • scan
│ missing stats
│ table: parent@primary
│ spans: [/'ap-southeast-2'/1 - /'ap-southeast-2'/1]
│
└── • scan
missing stats
table: parent@primary
spans: [/'ca-central-1'/1 - /'ca-central-1'/1] [/'us-east-1'/1 - /'us-east-1'/1]

# We don't yet support locality optimized search for semi join.
query T
Expand Down Expand Up @@ -1035,6 +1045,53 @@ SELECT * FROM [EXPLAIN DELETE FROM parent WHERE p_id = 1] OFFSET 2
└── • scan buffer
label: buffer 1

# An insert FK check only needs to search a single region when the region is a
# computed column dependent on the FK column and a constant value is inserted.
statement ok
CREATE TABLE parent_comp (
pk INT PRIMARY KEY,
crdb_region crdb_internal_region AS (
CASE WHEN pk <= 10 THEN 'us-east-1' ELSE 'ap-southeast-2' END
) STORED,
FAMILY (pk, crdb_region)
) LOCALITY REGIONAL BY ROW;

statement ok
CREATE TABLE child_comp (
pk INT PRIMARY KEY,
p_pk INT REFERENCES parent_comp (pk),
crdb_region crdb_internal_region AS (
CASE WHEN pk <= 10 THEN 'us-east-1' ELSE 'ap-southeast-2' END
) STORED,
FAMILY (pk, p_pk, crdb_region)
) LOCALITY REGIONAL BY ROW;

query T
SELECT * FROM [EXPLAIN INSERT INTO child_comp VALUES (1, 1)] OFFSET 2
----
·
• root
│
├── • insert
│ │ into: child_comp(pk, p_pk, crdb_region)
│ │
│ └── • values
│ size: 4 columns, 1 row
│
└── • constraint-check
│
└── • error if rows
│
└── • cross join (anti)
│
├── • values
│ size: 1 column, 1 row
│
└── • scan
missing stats
table: parent_comp@primary
spans: [/'us-east-1'/1 - /'us-east-1'/1]

# Tests creating a index and a unique constraint on a REGIONAL BY ROW table.
statement ok
CREATE INDEX new_idx ON regional_by_row_table(a, b)
Expand Down
46 changes: 46 additions & 0 deletions pkg/sql/opt/memo/expr.go
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Original file line number Diff line number Diff line change
Expand Up @@ -811,6 +811,52 @@ func (prj *ProjectExpr) InternalFDs() *props.FuncDepSet {
return &prj.internalFuncDeps
}

// FindInlinableConstants returns the set of input columns that are synthesized
// constant value expressions: ConstOp, TrueOp, FalseOp, or NullOp. Constant
// value expressions can often be inlined into referencing expressions. Only
// Project and Values operators synthesize constant value expressions.
func FindInlinableConstants(input RelExpr) opt.ColSet {
var cols opt.ColSet
if project, ok := input.(*ProjectExpr); ok {
for i := range project.Projections {
item := &project.Projections[i]
if opt.IsConstValueOp(item.Element) {
cols.Add(item.Col)
}
}
} else if values, ok := input.(*ValuesExpr); ok && len(values.Rows) == 1 {
tup := values.Rows[0].(*TupleExpr)
for i, scalar := range tup.Elems {
if opt.IsConstValueOp(scalar) {
cols.Add(values.Cols[i])
}
}
}
return cols
}

// ExtractColumnFromProjectOrValues searches a Project or Values input
// expression for the column having the given id. It returns the expression for
// that column.
func ExtractColumnFromProjectOrValues(input RelExpr, col opt.ColumnID) opt.ScalarExpr {
if project, ok := input.(*ProjectExpr); ok {
for i := range project.Projections {
item := &project.Projections[i]
if item.Col == col {
return item.Element
}
}
} else if values, ok := input.(*ValuesExpr); ok && len(values.Rows) == 1 {
tup := values.Rows[0].(*TupleExpr)
for i, scalar := range tup.Elems {
if values.Cols[i] == col {
return scalar
}
}
}
panic(errors.AssertionFailedf("could not find column to extract"))
}

// ExprIsNeverNull makes a best-effort attempt to prove that the provided
// scalar is always non-NULL, given the set of outer columns that are known
// to be not null. This is particularly useful with check constraints.
Expand Down
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