![]() "Special Instructions" VARCHAR2(4000) PATH '$."Special Instructions"',ĭescription VARCHAR(4000) PATH '$.Part.Description'))) AS "JT" Path expressions, to target the object fields that are projectedĭescription PATH Part.Description))) AS "JT" SELECT jt.* Separate arguments of a JSON column-expression and a SQL/JSONĮxplicit PATH clauses with SQL/JSON column Regardless of whether they are quoted, they are interpreted case-sensitivelyįor purposes of establishing the default path (the path used when there is no explicit In the first query the column names are writtenĮxactly the same as the names of the targeted object fields, including with respect to (Identifier Special Instructions contains Special Instructions, whose SQL identifier is quoted, the SQL column Theįirst query uses the simple, dot-notation syntax for the expressions that target the row andĬolumn data. This example uses json_table for two equivalent queries. These queries areĮxample 18-1 illustrates the difference between using the simple dot notation and usingĮxample 18-1 Equivalent JSON_TABLE Queries: Simple and Targets the entire document, you can omit the path part. )Īnd in cases where the row path expression is only '$', which Json_table( t.j.ShippingInstructions.Phone. Json_table( t.j, '$.ShippingInstructions.Phone'. View column together with a simple path to the targeted JSON data. The COLUMNS clause is still required.) Dot notation specifies a table or ![]() The default error handler for both levels is NULL ON ERROR.Īs an alternative to passing the context-item argument and the row pathĮxpression, you can use simple dot-notation syntax. When present, a column error handler overrides row-level error Handling for json_table, corresponding to the two levels of pathĮxpressions: row and column. Json_table is the SQL/JSON row path expression followed by an optionalĮrror clause for handling the row and the (required) COLUMNS clause, whichĭefines the columns of the virtual table to be created. The result of evaluating the expression is used as the context item for evaluating It canīe a table or view column value, a PL/SQL variable, or a bind variable with proper casting. The first argument to json_table is a SQL expression. Rows, as determined by evaluating the row path expression against the input document. Source table in the FROM list, whose rows each contain a JSON document that ![]() ![]() Typically a json_table invocation is laterally joined, implicitly, with a The columns of each generated row are defined by theĬolumn path expressions of the COLUMNS clause. Generates a row of virtual-table data for each JSON value selected by a row pathĮxpression (row pattern). To change the schema, just redefine the view - no need to The view exposes only data that conforms to the mapping Restriction on the kind of JSON documents that can be stored in the database (other thanīeing well-formed JSON data). This mapping is after the fact: the underlying JSONĭata can be defined and created without any regard to a schema or any particular pattern of Programmers operate on JSON data without consideration of the syntax of JSON or JSON pathĭefining a view over JSON data in effect maps a kind of ![]() You can use suchĪ view just as you would use any table or view. Use of json_table is to create a view of JSON data. You can query it using SQL - in a join expression, for example. You can then insert this virtual table into a pre-existing database table, or ![]()
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