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使用 Cypher 生成 Cypher 语句以重新创建索引和约束

以下内容可用于从现有数据库中提取索引定义和约束定义，并将生成的输出回放至另一个 Neo4j 数据库。例如，使用:play movies数据集（如从 Neo4j 浏览器运行时），我们可以定义以下索引和约束

// create a schema index on :Movie(title)
// 4.0 syntax
create index movieTitles for (n:Movies) on (n.title);
//
// or 3.x syntax and a schema index on :Person(name)
create index on :Person(name);
//
// create a constraint on :Movie such that no 2 Movies have the same tagline
create constraint on (n:Movie) assert (n.tagline) is unique;

并且使用上述数据集，将生成以下内容

3.x（注意，输出仅包含 2 个索引，因为上面的第一个索引语句采用 4.x 格式，并且无法在 3.x 上运行）

所有索引
neo4j> call db.indexes();
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| description                | indexName       | tokenNames | properties  | state    | type                   | progress | provider                              | id | failureMessage |
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| "INDEX ON :Person(name)"   | "Unnamed index" | ["Person"] | ["name"]    | "ONLINE" | "node_label_property"  | 100.0    | {version: "1.0", key: "native-btree"} | 1  | ""             |
| "INDEX ON :Movie(tagline)" | "index_3"       | ["Movie"]  | ["tagline"] | "ONLINE" | "node_unique_property" | 100.0    | {version: "1.0", key: "native-btree"} | 3  | ""             |
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

2 rows available after 244 ms, consumed after another 12 ms
所有约束
neo4j> call db.constraints();
+----------------------------------------------------------------+
| description                                                    |
+----------------------------------------------------------------+
| "CONSTRAINT ON ( movie:Movie ) ASSERT movie.tagline IS UNIQUE" |
+----------------------------------------------------------------+

1 row available after 13 ms, consumed after another 1 ms

4.0.x

所有索引
neo4j> call db.indexes();
+---------------------------------------------------------------------------------------------------------------------------------------------------+
| id | name                  | state    | populationPercent | uniqueness  | type    | entityType | labelsOrTypes | properties  | provider           |
+---------------------------------------------------------------------------------------------------------------------------------------------------+
| 3  | "constraint_e7afa4cc" | "ONLINE" | 100.0             | "UNIQUE"    | "BTREE" | "NODE"     | ["Movie"]     | ["tagline"] | "native-btree-1.0" |
| 2  | "index_5c0607ad"      | "ONLINE" | 100.0             | "NONUNIQUE" | "BTREE" | "NODE"     | ["Person"]    | ["name"]    | "native-btree-1.0" |
| 1  | "movieTitles"         | "ONLINE" | 100.0             | "NONUNIQUE" | "BTREE" | "NODE"     | ["Movies"]    | ["title"]   | "native-btree-1.0" |
+---------------------------------------------------------------------------------------------------------------------------------------------------+

3 rows available after 16 ms, consumed after another 1 ms
所有约束
neo4j> call db.constraints();
+------------------------------------------------------------------------------------------+
| name                  | description                                                      |
+------------------------------------------------------------------------------------------+
| "constraint_e7afa4cc" | "CONSTRAINT ON ( movie:Movie ) ASSERT (movie.tagline) IS UNIQUE" |
+------------------------------------------------------------------------------------------+

1 row available after 10 ms, consumed after another 6 ms

3.x 要导出索引和约束的 DROP 和 CREATE 语句，可以运行

CALL db.indexes() YIELD description
RETURN 'CREATE ' + description + ';'   ;

要提取 Cypher CREATE CONSTRAINT 语句，请运行

CALL db.constraints() YIELD description
RETURN 'CREATE ' + description + ';' ;

4.0.x

neo4j> call db.schemaStatements();
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| name                  | type         | createStatement                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | dropStatement                           |
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| "movieTitles"         | "INDEX"      | "CALL db.createIndex('movieTitles', ['Movies'], ['title'], 'native-btree-1.0', {`spatial.cartesian-3d.min`: [-1000000.0, -1000000.0, -1000000.0],`spatial.cartesian.min`: [-1000000.0, -1000000.0],`spatial.wgs-84.min`: [-180.0, -90.0],`spatial.cartesian-3d.max`: [1000000.0, 1000000.0, 1000000.0],`spatial.cartesian.max`: [1000000.0, 1000000.0],`spatial.wgs-84-3d.min`: [-180.0, -90.0, -1000000.0],`spatial.wgs-84-3d.max`: [180.0, 90.0, 1000000.0],`spatial.wgs-84.max`: [180.0, 90.0]})"                               | "DROP INDEX `movieTitles`"              |
| "constraint_e7afa4cc" | "CONSTRAINT" | "CALL db.createUniquePropertyConstraint( 'constraint_e7afa4cc', ['Movie'], ['tagline'], 'native-btree-1.0', {`spatial.cartesian-3d.min`: [-1000000.0, -1000000.0, -1000000.0],`spatial.cartesian.min`: [-1000000.0, -1000000.0],`spatial.wgs-84.min`: [-180.0, -90.0],`spatial.cartesian-3d.max`: [1000000.0, 1000000.0, 1000000.0],`spatial.cartesian.max`: [1000000.0, 1000000.0],`spatial.wgs-84-3d.min`: [-180.0, -90.0, -1000000.0],`spatial.wgs-84-3d.max`: [180.0, 90.0, 1000000.0],`spatial.wgs-84.max`: [180.0, 90.0]} )" | "DROP CONSTRAINT `constraint_e7afa4cc`" |
| "index_5c0607ad"      | "INDEX"      | "CALL db.createIndex('index_5c0607ad', ['Person'], ['name'], 'native-btree-1.0', {`spatial.cartesian-3d.min`: [-1000000.0, -1000000.0, -1000000.0],`spatial.cartesian.min`: [-1000000.0, -1000000.0],`spatial.wgs-84.min`: [-180.0, -90.0],`spatial.cartesian-3d.max`: [1000000.0, 1000000.0, 1000000.0],`spatial.cartesian.max`: [1000000.0, 1000000.0],`spatial.wgs-84-3d.min`: [-180.0, -90.0, -1000000.0],`spatial.wgs-84-3d.max`: [180.0, 90.0, 1000000.0],`spatial.wgs-84.max`: [180.0, 90.0]})"                             | "DROP INDEX `index_5c0607ad`"           |
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

3 rows available after 24 ms, consumed after another 7 ms