ReshmaAhamed Shingare

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance

An index is an on-disk structure associated with a table or view that speeds retrieval of rows from the table or view. An index contains keys built from one or more columns in the table or view. These keys are stored in a structure (B-tree) that enables SQL Server to find the row or rows associated with the key values quickly and efficiently.

A table or view can contain the following types of indexes:

Both clustered and nonclustered indexes can be unique. This means no two rows can have the same value for the index key. Otherwise, the index is not unique and multiple rows can share the same key value. For more information, see Create unique indexes.

Indexes are automatically maintained for a table or view whenever the table data is modified.

See Indexes for additional types of special purpose indexes.

Indexes are automatically created when PRIMARY KEY and UNIQUE constraints are defined on table columns. For example, when you create a table with a UNIQUE constraint, Database Engine automatically creates a nonclustered index. If you configure a PRIMARY KEY, Database Engine automatically creates a clustered index, unless a clustered index already exists. When you try to enforce a PRIMARY KEY constraint on an existing table and a clustered index already exists on that table, SQL Server enforces the primary key using a nonclustered index.

For more information, see Create primary keys and Create unique constraints.

Well-designed indexes can reduce disk I/O operations and consume fewer system resources therefore improving query performance. Indexes can be helpful for a variety of queries that contain SELECT, UPDATE, DELETE, or MERGE statements. Consider the query SELECT Title, HireDate FROM HumanResources.Employee WHERE EmployeeID = 250 in the AdventureWorks2019 database. When this query is executed, the query optimizer evaluates each available method for retrieving the data and selects the most efficient method. The method may be a table scan, or may be scanning one or more indexes if they exist.

When performing a table scan, the query optimizer reads all the rows in the table, and extracts the rows that meet the criteria of the query. A table scan generates many disk I/O operations and can be resource intensive. However, a table scan could be the most efficient method if, for example, the result set of the query is a high percentage of rows from the table.

When the query optimizer uses an index, it searches the index key columns, finds the storage location of the rows needed by the query and extracts the matching rows from that location. Generally, searching the index is much faster than searching the table because unlike a table, an index frequently contains very few columns per row and the rows are in sorted order.

With the plethora of characters that players can mix and match to get their perfect formation, Eira is a must-have in your formation. Essentially, she is a four-star controller that is insanely strong when she is combined with a DPS and other Espers and will dominate in battles!

Her unique abilities allow her to abuse them in combat when she can apply the potent “Speed Down” and “AP Down” debuffs on enemies which make them a hell of a lot more vulnerable and susceptible to taking damage from the DPS. Eira is mostly on the sidelines debuffing opponents so that the main damage dealer can obliterate them.

When she uses her S3, she will also reset the cooldown timer of her S2 skill, which allows her to apply the “AP Up” buff on anyone chosen Esper. Alongside that, she will also cleanse the fellow Esper of any sort of debuffs that might have been applied to them from the enemy’s end.

She dominates enemies like the Kronos and also the Temporal Tower, and Eira in Dislyte is also pretty good at clearing the Cube Miracle. Just like Eira, Jacob is another impeccable Esper, so make sure to check out our Dislyte Jacob Build Guide!

Eira has three main particular skills being known as her S1, S2, and S3 skills in Dislyte alongside her also having a captain ability. When mentioning starter capable Espers, we can’t skip over Drew, therefore read up on our Dislyte Drew Esper Guide!

The first Dislyte Eira skill features her “Chords of Heron” skill which entails her being able to unleash damage that is equivalent to 120% of her base attack. Alongside that, there is a 70% chance that she will be able to provide a gracious “Speed Up” buff to her fellow Espers.

Level 2 of the Eira Skill will buff up the overall damage output to 105%, while level 3 will enhance the trigger chance to 60%. With that, level 4 will increase the damage output by 110%, while level 5 will enhance the trigger chance by 70%. Lastly, maxing out the skill will increase the overall damage by 120%.

The second skill of Eira in Dislyte is pretty useful as well. Upon casting it, she will be able to purify her fellow Espers from any kind of debuffs that might have been applied to them from the enemy’s end. With that, she will also grant her teammates the “Brisingamen’s Watch” for a total of 2 turns. The cooldown for Divine Love is 3 turns. Another excellent support like Eira is Berenice, so read our Dislyte Berenice Guide!

With this skill in hand, Eira Esper can unleash damage to enemies that equates to 120% of her base attack, while she will also apply the “Speed Down” debuff to enemies for a total of 2 turns while also decreasing their AP by 30%. With that, she will also reset Divine Love’s overall cooldown for the skill.

Leveling it up to levels 2, 3 4, and 5 will increase the overall damage in this order: 95% at level 2, 100% at level 3, 110% at level 4, and 120% at level 5. Maxing out Seabreeze Sonata will reduce the cooldown of this skill by a total of 1 turn. If you’re looking for fighters to go along with Eira, then our Dislyte Mona Guide should convince you to build Mona!

When it comes to her captain ability, she will simply enhance the overall attack output for all Esper by 24%.

As we’ve mentioned before in our other guides, all Espers in Dislyte will have six main ascension phases that players are highly advised to level up as soon as they start building the Esper. The main reason for that is that it will buff up their Defense, HP, as well as offer a major boost to one of their abilities when the Esper has been upgraded to phase 3.

Below listed are the six main ascension phases that cater to Eira and help her become even stronger support in gameplay. You might like our Dislyte Tang Xuan Build if you want more variety for Espers to check out!

For Eira to perform her duties as support in Dislyte, she is going to need relics that support her and provide for the extra buffs that make her all the stronger and help her become overpowered. If you are completely unaware of how relics work, then you might wanna educate yourself by reading our Dislyte Relic Guide!

Starting things off with the first most popular set chosen by the player base, it is the Wind Walker Set x4, which will essentially provide Eira with 25% enhanced speed, which is important for her since she needs the swiftness in combat. Below are the recommended four pieces with their sub-stats too:

As for the two-piece set, Eira’s best slot set would be the Apollo’s Bow Set x2 which will provide her with an ACC buff by 25%, which is pretty important for her when she is being used as support in combat. After players reach a certain point in the game, they will definitely wouldn’t want to miss out on the Dislyte Gabrielle Guide!

Apart from the first main best in slot pieces, there are only two main sets that can benefit Esper Eira. the first one is going to be the War Machine Set x4, now, this is only for people who intend to make Dislyte Eira a hybrid build instead of the full support that she originally intended to be built like.

The war machine set can give her a 30% enhanced attack. Liling is one of the best Espers to pair up with Eira, so you might find our Dislyte Li Ling Guide interesting!

For the two-piece set, players can choose the Master Grove Set x2, which will essentially grant Eira an increased 25% HP, which is always welcome for her. For that reason alone, when giving her an attack relic set, it is always useful to pair it with a two-piece set that can fill in for the missed HP sets.

Another route that players can go for is combining different sets, such as players can go for the War Machine set but pair it with the Apollos Set x2, or even go for the Wind Walker Set x4 with the Master Grove Set x2. Looking to learn how to level Espers better? Why not take help from our Dislyte Best Leveling Guide for Espers!

If there are players that are for some reason looking to main as Eira, then they should consider taking a look at her overall performance across all types of story content, ranging from story stages, cube miracle, and different dungeons and difficult bosses.

With that, we will wrap up with our Dislyte Eira Esper guide, let us know what you think! Before starting on building Espers, you might wanna know how Dislyte itself works, therefore check our Dislyte Guide for Beginners guide!