site/contents/reference-dstore.md
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----- content-type: "page" title: "dstore Module" ----- {@ _defs_.md || 0 @} {#op||dsdelete||{{dstore}} {{sl}}||{{dstore}}|| Removes an item from the datastore {{dstore}}. The item is uniquely identified by {{sl}}, which contains the collection containing the item and the item id, separated by a forward slash (/). Puts the reference to the modified datastore back on tbe stack. #} {#op||dsget||{{dstore}} {{sl}}||{{d}}|| Retrieves item {{d}} from datastore {{dstore}}. {{d}} is retrieved by specifying {{sl}}, which contains the collection containing the item and the item id, separated by a forward slash (/). #} {#op||dsinit||{{sl}}||{{dstore}}|| Initializes a bew datastore by creating the {{sl}} JSON file. Puts the datastore instance on the stack. #} {#op||dspost||{{dstore}} {{sl}} {{d}}||{{dstore}}|| Adds the dictionary {{d}} to the datastore {{dstore}} inside collection {{sl}}, generating and adding a unique **id** field to {{d}}. If the collection {{sl}} does not exist it is created. Puts the reference to the modified datastore back on tbe stack. #} {#op||dsput||{{dstore}} {{sl}} {{d}}||{{dstore}}|| Adds the dictionary {{d}} to the datastore {{dstore}}. {{sl}} contains the collection where {{d}} will be placed and the id of {{d}}, separated by a forward slash (/). If the collection {{sl}} does not exist it is created. Puts the reference to the modified datastore back on tbe stack. #} {#op||dsquery||{{dstore}} {{sl}} {{q}}||({{d0p}})|| > Retrieves a quotation of dictionaries from the collection {{sl}} of datastore {{dstore}} obtained by applying {{q}} as a filter to each item of the collection, picking only the elements that match the filter. > > > %sidebar% > > Example > > > > Assuming that **ds** is a datastore, the following program retrieves all elements of teh collection **posts** whose author field is set to "h3rald": > > > > ds "posts" ('author dget "h3rald" ==) dsquery #} {#op||dsread||{{sl}}||{{dstore}}|| Reads the previously-created datastore from the file {{sl}} and puts the resulting datastore instance on the stack. #} {#op||dswrite||{{dstore}}||{{dstore}}|| Writes the contents of the datastore {{dstore}} to the filesystem. #} |