Abstract:
Techniques and structures for tuning database queries. Actual statistics associated with data stored are retrieved from at least one memory device. The data is associated with one or more tenants of the multi-tenant database system. The actual statistics include at least one type of statistic maintained for the data. A subset of the actual statistics is selected based on a data trait targeted for optimization. A statistical value is calculated for each actual statistic from the subset of actual statistics across one or more tenants having the data trait targeted for optimization. An optimal query plan is determined based on the original query and the calculated statistical values.
Abstract:
In an on demand database system, a query engine applies a custom index for inner queries. The query engine receives a query and determines that the query has an inner query nested within the primary query. The query engine identifies that a custom index exists for a client associated with the query, and applies the custom index to filter results for the query. The custom index includes a subset of information of a table that includes accounts for multiple different clients. By using the custom index, the query engine can filter the results more efficiently that if solely using the multiple client table.
Abstract:
In accordance with embodiments, there are provided mechanisms and methods for query optimization in a database system. These mechanisms and methods for query optimization in a database system can enable embodiments to optimize OR expression filters referencing different logical tables. The ability of embodiments to optimize OR expression filters referencing different logical tables can enable optimization that is dynamic and specific to the particular tenant for whom the query is run and improve the performance and efficiency of the database system in response to query requests.
Abstract:
Techniques and structures for tuning database queries. Actual statistics associated with data stored are retrieved from at least one memory device. The data is associated with one or more tenants of the multi-tenant database system. The actual statistics include at least one type of statistic maintained for the data. A subset of the actual statistics is selected based on a data trait targeted for optimization. A statistical value is calculated for each actual statistic from the subset of actual statistics across one or more tenants having the data trait targeted for optimization. An optimal query plan is determined based on the original query and the calculated statistical values.
Abstract:
Techniques and structures for tuning database queries. Actual statistics associated with data stored are retrieved from at least one memory device. The data is associated with one or more tenants of the multi-tenant database system. The actual statistics include at least one type of statistic maintained for the data. A subset of the actual statistics is selected based on a data trait targeted for optimization. A statistical value is calculated for each actual statistic from the subset of actual statistics across one or more tenants having the data trait targeted for optimization. An optimal query plan is determined based on the original query and the calculated statistical values.
Abstract:
In a method, system, and computer-readable medium having instructions for executing a query in a database system, a query request is received with a query predicate to filter data returned in response to the query request and the query predicate has a formula, the query request is transformed to a transformed query request by preprocessing the formula in the query predicate, and the query request is optimized using the transformed query request.
Abstract:
In a method, system, and computer-readable medium having instructions for executing a query in a database system, a query request is received with a query predicate to filter data returned in response to the query request and the query predicate has a formula, the query request is transformed to a transformed query request by preprocessing the formula in the query predicate, and the query request is optimized using the transformed query request.
Abstract:
Methods and systems are described for creating a custom index in a multi-tenant database environment. In one embodiment, a method includes obtaining query for a multi-tenant database that is recommended as a candidate for creating an additional filter, evaluating the query against criteria to determine whether to select the query for creating the additional filter, and creating the additional filter for the query, if the query is selected.
Abstract:
In accordance with embodiments, there are provided mechanisms and methods for query optimization in a database system. These mechanisms and methods for query optimization in a database system can enable embodiments to optimize OR expression filters referencing different logical tables. The ability of embodiments to optimize OR expression filters referencing different logical tables can enable optimization that is dynamic and specific to the particular tenant for whom the query is run and improve the performance and efficiency of the database system in response to query requests.